GARNet Research Roundup: June 26th 2020

This edition of the GARNet Research Roundup begins with a study from Nottingham and Leeds that looks at the much-neglected subject of the control of floral arrest. The second paper from Edinburgh identifies a signaling role for the co-opted transposable elements ALP1 and ALP2 in Arabidopsis. Hans-Wilhelm Nützmann from the University of Bath leads the next study that looks at the co-regulation of clustered biosynthetic pathway genes. The fourth paper is from Cambridge and looks at the role of the ASY1 protein during meiotic recombination. The next paper is from Durham and looks at the role of GA-regulated DELLA proteins in the regulation of stomatal aperature.

The next five papers have a methods-type application that should be useful to other researchers. Firstly a research team led from Oxford highlights an improved protocol for the proteome-analysis technique of RNA interactome capture. Secondly researchers from UEA introduce the NATpare tool, which is a pipeline for high-throughput prediction and functional analysis of nat-siRNAs. The third ‘methods’ paper is from the University of Warwick where they have developed novel markers for protoplast-based analyses of hormone signaling. The fourth paper is a protocol for using CRISPR-Cas9 gene editing in Brachypodium. The final ‘methods-type’ paper is from Alison Smith’s group in Cambridge and has developed a riboswitch-based resource for use in the model alga Chlamydomonas reinhardtii.

The eleventh paper is led from the University of Glasgow and looks at the activity of the circadian clock in Arabidopsis roots. The next paper introduces genes from the parasitic plant Striga hermonthica into Arabidopsis to show that strigolactone signaling can replace GA signaling in the control of seed germination. The final two papers are focused on research in wheat, first led from the University of Leicester that looks at recombination in durum wheat and secondly from Rothamsted in which they have identified a whole family of NPF membrane transporter genes.

Ware A, Walker CH, Šimura J, et al (2020) Auxin export from proximal fruits drives arrest in temporally competent inflorescences Nat Plants. 2020;10.1038/s41477-020-0661-z. doi:10.1038/s41477-020-0661-z

Open Access with this link

Al Ware and Catriona Walker are co-first authors on this study from the Universities of Nottingham and Leeds. They have looked at the factors that control the timing of floral arrest in Arabidopsis. They discover that there is a minimum number and optimal positioning of fruits that is necessary for floral arrest, as well as looking into the role of auxin transport in this process.

Velanis CN, Perera P, Thomson B, et al (2020) The domesticated transposase ALP2 mediates formation of a novel Polycomb protein complex by direct interaction with MSI1, a core subunit of Polycomb Repressive Complex 2 (PRC2) PLoS Genet. 2020;16(5):e1008681. doi:10.1371/journal.pgen.1008681

Open Access

Christos Velanis is first author on this research led by the Goodrich group at the University of Edinburgh that looked at the function of the Arabidopsis ANTAGONIST OF LIKE HETEROCHROMATIN PROTEIN 1 (ALP1) gene, which has arose by domestication of the Harbinger class of transposable elements (TEs). ALP1 is a component of the POLYCOMB REPRESSIVE COMPLEX 2 (PRC2) but yet its functional significance is not yet known. They also identify the related ALP2 gene and find that it interacts with MULTICOPY SUPPRESSOR OF IRA1 (MSI1) as part of the PRC2.

Nützmann HW, Doerr D, Ramírez-Colmenero A, et al (2020) Active and repressed biosynthetic gene clusters have spatially distinct chromosome states Proc Natl Acad Sci U S A. 2020;201920474. doi:10.1073/pnas.1920474117

Hans-Wilhelm Nützmann is a now a member of faculty at the University of Bath but led this research as a member of the Osbourn group at the John Innes Centre. They use Hi-C and related techniques to study the control of expression of clustered biosynthetic pathway genes in Arabidopsis. This study reveals potential mechanisms that suggest gene clustering in the one-dimensional chromosome is accompanied by compartmentalization of the 3D chromosome.

Lambing C, Kuo PC, Tock AJ, Topp SD, Henderson IR (2020) ASY1 acts as a dosage-dependent antagonist of telomere-led recombination and mediates crossover interference in Arabidopsis Proc Natl Acad Sci U S A. 2020;201921055. doi:10.1073/pnas.1921055117

Open Access

Christophe Lambing is first author on this study from the Henderson lab at the University of Cambridge that investigates the role of the ASY1 protein in the control of recombination frequency during meiosis. ASY1 is localized in an ascending telomere-to-centromere gradient and this informs the role that it plays to antagonize telomere-recombination to ensure this occurs in more gene-rich regions of the chromosomes.

Sukiran NA, Steel PG, Knight MR (2020) Basal stomatal aperture is regulated by GA-DELLAs in Arabidopsis J Plant Physiol. 2020;250:153182. doi:10.1016/j.jplph.2020.153182

Nur Afiqah Sukiran is the first author of this study from the Durham University that investigates the role of DELLA proteins in the regulation of stomatal aperature. They also find that the GID1 gibberellin receptor is necessary for optimal basal stomatal aperture.

Professor Marc Knight will be discussing his labs work on the #GARNetPresents webinar on June 30th 2020

Bach-Pages M, Homma F, Kourelis J, et al (2020) Discovering the RNA-Binding Proteome of Plant Leaves with an Improved RNA Interactome Capture Method. Biomolecules. 2020;10(4):661 doi:10.3390/biom10040661

Open Access

Marcel Bach-Pages is first author on this research led from the University of Oxford that has improved the proteome-analysis technique of RNA interactome capture (RIC) to identify 717 RNA Binding Proteins (RBP) from Arabidopsis. Many of these RBPs exhibit unconventional modes of RNA binding and uncovered greater diversity in the number of proteins for which RNA binding is an important part of their function.

Thody J, Folkes L, Moulton V (2020) NATpare: a pipeline for high-throughput prediction and functional analysis of nat-siRNAs Nucleic Acids Res. 2020;gkaa448. doi:10.1093/nar/gkaa448

Joshua Thody leads this work from the University of East Anglia in which the authors present a new software pipeline, called NATpare, for prediction and functional analysis of Natural antisense transcript-derived small interfering RNAs (nat-siRNAs) using sRNA and degradome sequencing data. Although this tool could be used to analyse data from different experimental systems it is benchmarked using Arabidopsis data and the authors show that it could rapidly identify a comprehensive set of nat-siRNAs from different tissues and that are produced in response to different stresses.

Lehmann S, Dominguez-Ferreras A, Huang WJ, Denby K, Ntoukakis V, Schäfer P (2020) Novel markers for high-throughput protoplast-based analyses of phytohormone signaling. PLoS One. 2020;15(6):e0234154. doi:10.1371/journal.pone.0234154

Open Access

Silke Lehmann leads this work from the University of Warwick that has generated a community-resource of 18 promoter::luciferase constructs that respond to different phytohormones. In addition they suggest an experimental setup for high-throughput analyses in which these new reporter constructs might be used to screen for biological and environmental stimuli that effect hormone-mediated gene expression.

Hus K, Betekhtin A, Pinski A, et al (2020) A CRISPR/Cas9-Based Mutagenesis Protocol for Brachypodium distachyon and Its Allopolyploid Relative, Brachypodium hybridum. Front Plant Sci. 2020;11:614. doi:10.3389/fpls.2020.00614 Open Access

This Polish project is led by Karolina Hus and includes co-authors from Cambridge and Aberystwyth. They have developed a protocols for CRISPR-Cas9 gene editing in Brachypodia species. As proof of concept they target two cyclin-dependent kinases (CDKG1 and CDKG2) that are involved in DNA recombination.

Mehrshahi P, Nguyen GTDT, Gorchs Rovira A, et al (2020) Development of Novel Riboswitches for Synthetic Biology in the Green Alga Chlamydomonas ACS Synth Biol. 2020;10.1021/acssynbio.0c00082. doi:10.1021/acssynbio.0c00082

Open Access

Payam Mehrshahi is the first author on this Academia-Industry collaboration led from the University of Cambrige. They have used a synthetic biology approach to assess the effectiveness of riboswitchs (RNA regulatory elements) in the control of gene expression in the model alga Chlamydomonas reinhardtii.

Nimmo HG, Laird J, Bindbeutel R, Nusinow DA (2020) The evening complex is central to the difference between the circadian clocks of Arabidopsis thaliana shoots and roots Physiol Plant. 2020;10.1111/ppl.13108. doi:10.1111/ppl.13108 Open Access

Hugh Nimmo from the University of Glasgow is lead author on this UK-USA collaboration that has looked at the operation of the circadian clock in root tissues and in particularly how it responds to light quality. They found that plants with mutations in certain genes that make up the circadian clock evening complex have root-specific effects, confirming that the shoot and root clocks response to differently to light signals.

Bunsick M, Toh S, Wong C, et al (2020) SMAX1-dependent seed germination bypasses GA signalling in Arabidopsis and Striga Nat Plants. 2020;10.1038/s41477-020-0653-z. doi:10.1038/s41477-020-0653-z

Michael Bunsick is first author of this Canadian-led study that includes Julie Scholes from the University of Sheffield as a co-author. Leading from a curiosity about the relationship between host root exudates and the parasitic plant Striga hermonthica, they were led to find that expression of Striga strigolactone-hormone receptor proteins in Arabidopsis is able to bypass the requirement for GA in seed germination. This demonstrates both how the Striga might sense host signals and that there is no absolute requirement for GA-during seed germination.

Desjardins SD, Ogle DE, Ayoub MA, et al (2020) MutS homologue 4 and MutS homologue 5 maintain the obligate crossover in wheat despite stepwise gene loss following polyploidization Plant Physiol. 2020;pp.00534.2020. doi:10.1104/pp.20.00534

Open Access

Stuart Desjardins is first author on his research led from the University of Leicester. They work with allotetraploid (AABB) durum wheat and show that this plant undergoes two pathways of meiotic recombination. They show that the class I pathway requires the MSH4 and MSH5 (MutSγ) proteins and the authors show that these genes are absent in hexaploid (AABBDD) wheat. These findings enable the authors to speculate about the function of these proteins in allopolyploid wheat.

Wang H, Wan Y, Buchner P, King R, Ma H, Hawkesford MJ (2020) Phylogeny and gene expression of the complete NITRATE TRANSPORTER 1/PEPTIDE TRANSPORTER FAMILY (NPF) in Triticum aestivum L J Exp Bot. 2020;eraa210. doi:10.1093/jxb/eraa210 Open Access

Huadun Wang is first author on this manuscript that is led from Rothamsted Research and includes Chinese collaborators. They investigate the 331 member family of wheat NPF genes that encode membrane transporters that transport a diverse range of substrates. Phylogenetically these wheat NPF genes are closely clustered with Arabidopsis, Brachypodium and rice orthologs and this study and lays the foundation for their further functional analysis in wheat.

GARNet Research Roundup: February 18th 2020

This weeks GARNet Research Roundup begins with two studies that characterize the role of proteins that are involved in the control of meiotic recombination. The first study is from the Henderson lab at the University of Cambridge and investigates the role of the REC8 protein whilst the second is from John Doonan’s group at Aberystwyth University and investigates the role of the cyclin-dependent kinase CDKG.

The third paper is from the same research group in Aberystwyth and investigates how alternative splicing can impact the function of the FLOWERING LOCUS M gene.

The next papers is a cross-UK collaboration led from Rothamsted Research and the John Innes Centre that identifies an important QTL associated with the generation of high-fibre wheat. The fifth paper is from the JIC and reveals how the immune resistance gene MLO plays a role in a plants association with beneficial microbial symbiotes.

The sixth paper is from the Gibbs lab at the University of Birmingham and further characterizes the function of the VRN2 component of the polycomb repressive complex 2.

Nick Harberd from Oxford is a corresponding author of the next paper, which identifies a new gene that could be used to improve nitrogen-use efficiency in rice.

The eighth paper is a proteomic-based study from the University of Cambridge that identifies novel stress-induced components of the Arabidopsis spliceosome.

The penultimate paper is from Jonathan Jones’ lab at the Sainsbury lab, Norwich in which they characterize a new transgenic line useful for studying the plant immune response.

The final paper includes Liam Dolan from Oxford as a co-author in a study that characterizes a novel ATPase from the algae Chara australis.

Lambing C, Tock AJ, Topp SD, Choi K, Kuo PC, Zhao X, Osman K, Higgins J, Franklin FCH, Henderson IR (2020) Interacting genomic landscapes of REC8-cohesin, chromatin and meiotic recombination in Arabidopsis thaliana. Plant Cell. doi: 10.1105/tpc.19.00866
Open Access

This study is led by Chris Lambing from Ian Henderson’s group at the University of Cambridge and includes collaborators from Leicester and Birmingham. They use ChIP-seq to identify the genomic regions associated with the REC8 protein, showing that it interacts with regions with multiple distinct chromatin states. This interaction plays a key role in controlling the formation of double strands breaks and is required to organize meiotic chromosome architecture and interhomolog recombination.

Nibau C, Lloyd AH, Dadarou D, Betekhtin A, Tsilimigka F, Phillips DW, Doonan JH (2020) CDKG1 Is Required for Meiotic and Somatic Recombination Intermediate Processing in Arabidopsis. Plant Cell. doi: 10.1105/tpc.19.00942 Open Access

Candida Nibau from Aberystwyth University leads this research that reveals a critical role for the cyclin-dependent kinase G1 (CDKG) in the control of recombination, both during meiosis and within somatic cells. The authors discover that this role occurs early in the process through the stabilization of recombination intermediates.

Nibau C, Gallemí M, Dadarou D, Doonan JH, Cavallari N (2020) Thermo-Sensitive Alternative Splicing of FLOWERING LOCUS M Is Modulated by Cyclin-Dependent Kinase G2. Front Plant Sci. doi: 10.3389/fpls.2019.01680 Open Access

Candida Nibau is first author on this collaboration between researchers in the UK (Aberystwyth University) and Vienna, Austria. They assess the factors that control the contribution of two splicing variants of the FLOWERING LOCUS M gene on flowering time across a temperature range. They find that this process is controlled by the activity of the cyclin-dependent kinase G2 (CDKG2) and its cognate cyclin, CYCLIN L1 (CYCL1).

Lovegrove A, Wingen LU, Plummer A, Wood A, Passmore D, Kosik O, Freeman J, Mitchell RAC, Hassall K, Ulker M, Tremmel-Bede K, Rakszegi M, Bedő Z, Perretant MR, Charmet G, Pont C, Salse J, Waite ML, Orford S, Burridge A, Pellny TK, Shewry PR, Griffiths S (2020) Identification of a major QTL and associated molecular marker for high arabinoxylan fibre in white wheat flour. PLoS One. doi: 10.1371/journal.pone.0227826
Open Access

Alison Lovegrove at Rothamsted Research is the first author on this cross-UK research that has gained significant interest from the main–stream media. Through analysis of a Chinese wheat variety with high dietary fibre due to the high amounts of cell wall polysaccharide arabinoxylan the authors identified a QTL that is responsible for this phenotype. Understanding this QTL will allow use of both marker-assisted breeding and new breeding technologies to aid in the generation of high yield, high fibre varieties.

Jacott CN, Charpentier M, Murray JD, Ridout CJ (2020) Mildew Locus O facilitates colonization by arbuscular mycorrhizal fungi in angiosperms. New Phytol. doi: 10.1111/nph.16465

Catherine Jacott is first author on this study from the JIC that investigates the role of the known barley resistance gene Mildew Resistance Locus O (MLO) during arbuscular mycorrhizal interactions in wheat, barley and Medicago. They show that MLO is important for this beneficial symbiotic association and that the role of MLO has been appropriated during infection with pathogenic powdery mildew.

Labandera AM, Tedds HM, Bailey M, Sprigg C, Etherington RD, Akintewe O, Kalleechurn G, Holdsworth MJ, Gibbs DJ (2020) The PRT6 N-degron pathway restricts VERNALIZATION 2 to endogenous hypoxic niches to modulate plant development. New Phytol. doi: 10.1111/nph.16477

Anne-Marie Labandera is first author on this work from Dan Gibbs’ lab in Birmingham. They show that ubiquitin-mediated proteolysis of the VERNALIZATION2 (VRN2) protein via the oxygen-dependent PRT6 N-degron pathway is important for many areas of plant development. This regulation of VRN2 has different developmental outcomes depending on whether it occurs in or out of meristematic tissues.

Wu K, Wang S, Song W, Zhang J, Wang Y, Liu Q, Yu J, Ye Y, Li S, Chen J, Zhao Y, Wang J, Wu X, Wang M, Zhang Y, Liu B, Wu Y, Harberd NP, Fu X (2020) Enhanced sustainable green revolution yield via nitrogen-responsive chromatin modulation in rice. Science. doi: 10.1126/science.aaz2046

Kun Wu is first author on this Chinese-led investigation that also includes Nick Harberd from Oxford University as a corresponding author. Working in rice they link genomic-wide chromatin changes with expression of the NGR5 (NITROGEN-MEDIATED TILLER GROWTH RESPONSE 5) transcription factor during nitrogen-induced growth. Overexpression of NGR5 can uncouple nitrogen-sensing from tiller production and therefore provide a novel tool to possibly enhance agricultural production in low nitrogen conditions.

Marondedze C, Thomas L, Lilley KS, Gehring C (2020) Drought Stress Causes Specific Changes to the Spliceosome and Stress Granule Components. Front Mol Biosci. doi: 10.3389/fmolb.2019.00163 Open Access

Claudius Marondedze is the first author on this collaboration between the University of Cambridge and KAUST in Saudi Arabia. They perform label-free mRNA interactome-capture to identify RNA interacting proteins that are induced after drought stress. This reveals over 40 novel spliceosome-interacting proteins but also 32 proteins that associate with stress granules, which are indicative of transcriptional arrest. This provides new insights into how plant stress responses might be altered by the activity of spliceosome components.

Ngou BPM, Ahn HK, Ding P, Redkar A, Brown H, Ma Y, Youles M, Tomlinson L, Jones JDG (2020) Estradiol-inducible AvrRps4 expression reveals distinct properties of TIR-NLR-mediated effector-triggered immunity. J Exp Bot. doi: 10.1093/jxb/erz571

This research from Jonathan Jones’ group at the Sainsbury Lab, Norwich is led by Bruno Pok Man Ngou. They have developed a transgenic line that enables the transient in planta expression of AvrRps4, which is a potent bacterial immune effector. This stimulates the RRS1/RPS4-dependent immune response and provides insights into certain mechanisms of this pathway without exposing the plants to pathogens.

Zhang S, Habets M, Breuninger H, Dolan L, Offringa R, van Duijn B (2020) Evolutionary and Functional Analysis of a Chara Plasma Membrane H(+)-ATPase. Front Plant Sci. doi: 10.3389/fpls.2019.01707 Open Access

Liam Dolan from the University of Oxford is a co-author on this Dutch-led research that includes Sutun Zhang as first author. They characterize a plasma membrane localised ATPase from the algae Chara australis and perform complementation studies in both yeast and Arabidopsis. These studies allow the authors to propose that the mode of regulation of this algal ATPase is likely different from that of known yeast and land plant PM H+-ATPases.

GARNet Research Roundup: September 24th 2019

Due to a significant delay this GARNet Research Roundup is a bumper overview of recent(ish) publications across discovery-led plant science, which have at least one contributor from a UK institution.

These can be (very) loosely separated into the following categories:

Circadian Clock: Greenwood et al, PloS Biology. Belbin et al, Nature Communications.

Environmental responses: Rodríguez-Celma et al, PNAS. Walker and Bennett, Nature Plants. Conn et al, PLoS Comput Biology. de Jong et al,PLoS Genetics. Molina-Contreras et al,The Plant Cell.

Defence signaling: Van de Weyer et al, Cell.Hurst et al, Scientific Reports. Xiao et al, Nature. Wong et al, PNAS.

Cell Biology: Miller et al, The Plant Cell. Coudert et al, Current Biology. Burgess et al,The Plant Cell. Harrington et al, BMC Plant Biology.

Metabolism: Jia et al, J Biol Chem. Perdomo et al, Biochem J. Gurrieri et al, Frontiers in Plant Science. Mucha et al, The Plant Cell. Atkinson et al, JXBot.

Cell Wall Composition: Wightman et al, Micron. Milhinhos et al, PNAS.

Signaling: Hartman et al, Nature Communications. Dittrich et al, Nature Plants. Villaécija-Aguilar et al, PLoS Genetics

Greenwood M, Domijan M, Gould PD, Hall AJW, Locke JCW (2019) Coordinated circadian timing through the integration of local inputs in Arabidopsis thaliana. PLoS Biol. 17(8):e3000407. doi: 10.1371/journal.pbio.300040 Open Access

Lead author is Mark Greenwood. UK contribution from The Sainsbury lab University of Cambridge, University of Liverpool and Earlham Institute. Using a mixture of experimental and modeling this paper shows that individual organs have circadian clocks that runs at different speeds.

Belbin FE, Hall GJ, Jackson AB, Schanschieff FE, Archibald G, Formstone C, Dodd AN (2019) Plant circadian rhythms regulate the effectiveness of a glyphosate-based herbicide. Nat Commun. 2019 Aug 16;10(1):3704. doi: 10.1038/s41467-019-11709-5 Open Access

Lead author is Fiona Belbin. UK contribution from University of Bristol and Syngenta Jealott’s Hill. Activity of the circadian clock determines that the plant response to the herbicide glyphosate is lessened at dusk, promoting the idea of agricultural chronotherapy. Fiona discusses this paper on the GARNet Community Podcast.

Rodríguez-Celma J, Connorton JM, Kruse I, Green RT, Franceschetti M, Chen YT, Cui Y, Ling HQ, Yeh KC, Balk J (2019) Arabidopsis BRUTUS-LIKE E3 ligases negatively regulate iron uptake by targeting transcription factor FIT for recycling. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.1907971116 Open Access

Lead author is Jorge Rodríguez-Celma. UK contribution from John Innes Centre, University of East Anglia.The Arabidopsis E3 ubiquitin ligases, BRUTUS-LIKE1 (BTSL1) and BTSL2 target the FIT transcription factor for degradation, altering the plant response to harmful level of iron.

Walker CH, Bennett T (2019) A distributive ‘50% rule’ determines floral initiation rates in the Brassicaceae. Nat Plants. doi: 10.1038/s41477-019-0503-z
Lead author Catriona Walker. UK contribution from the University of Leeds. The authors introduce the 50%-rule that defines the relationshop between the total number of flowers the number of secondary inflorescences

Conn A, Chandrasekhar A, Rongen MV, Leyser O, Chory J, Navlakha S (2019) Network trade-offs and homeostasis in Arabidopsis shoot architectures. PLoS Comput Biol. doi: 10.1371/journal.pcbi.100732 Open Access

Lead author is Adam Conn. UK contribution from Sainsbury Laboratory, University of Cambridge. This study performed 3D scanning of 152 Arabidopsis shoot architectures to investigate how plants make trade-offs between competing objectives.

de Jong M, Tavares H, Pasam RK, Butler R, Ward S, George G, Melnyk CW, Challis R, Kover PX, Leyser O (2019) Natural variation in Arabidopsis shoot branching plasticity in response to nitrate supply affects fitness. PLoS Genet. doi: 10.1371/journal.pgen.1008366 Open Access

Lead author is Maaike de Jong. UK contribution from the Sainsbury Laboratory, University of Cambridge, the University of York and the University of Bath. This study looks at phenotypic plasticity of shoot branching in Arabidopsis diversity panels grown until different nitrate concentrations.

Molina-Contreras MJ, Paulišić S, Then C, Moreno-Romero J, Pastor-Andreu P, Morelli L, Roig-Villanova I, Jenkins H, Hallab A, Gan X, Gómez-Cadenas A, Tsiantis M, Rodriguez-Concepcion M, Martinez-Garcia JF (2019) Photoreceptor Activity Contributes to Contrasting Responses to Shade in Cardamine and Arabidopsis Seedlings. Plant Cell. doi: 10.1105/tpc.19.00275 Open Access

Lead author is Maria Jose Molina-Contreras. UK contribution from the University of Oxford. The authors looks at the response to different light conditions and how they contribute to phenotypic determination in Cardamine and Arabidopsis seedlings.

Van de Weyer AL, Monteiro F, Furzer OJ, Nishimura MT, Cevik V, Witek K, Jones JDG, Dangl JL, Weigel D, Bemm F (2019) A Species-Wide Inventory of NLR Genes and Alleles in Arabidopsis thaliana. Cell. doi: 10.1016/j.cell.2019.07.038 Open Access

Lead author is Anna-Lena Van de Weyer. UK contribution from The Sainsbury Laboratory, Norwich. Using sequence enrichment and long-read sequencing the authors present the pan-NLRome constructed from 40 Arabidopsis accessions.

Hurst CH, Wright KM, Turnbull D, Leslie K, Jones S, Hemsley PA (2019) Juxta-membrane S-acylation of plant receptor-like kinases is likely fortuitous and does not necessarily impact upon function. Sci Rep. doi: 10.1038/s41598-019-49302-x Open Access

Lead author is Charlotte Hurst. UK contribution from the James Hutton Institute and the University of Dundee. They look at the functional role of post-translational modification S-acylation with a focus on the plant pathogen perceiving receptor-like kinase FLS2.

Xiao Y, Stegmann M, Han Z, DeFalco TA, Parys K, Xu L, Belkhadir Y, Zipfel C, Chai J (2019) Mechanisms of RALF peptide perception by a heterotypic receptor complex. Nature. doi: 10.1038/s41586-019-1409-7
Lead author is Yu Xiao. UK contribution from The Sainsbury Laboratory, Norwich. This study investigates how RAPID ALKALINIZATION FACTOR (RALF) peptides induce receptor complex formation to regulate immune signaling.

Wong JEMM, Nadzieja M, Madsen LH, Bücherl CA, Dam S, Sandal NN, Couto D, Derbyshire P, Uldum-Berentsen M, Schroeder S, Schwämmle V, Nogueira FCS, Asmussen MH, Thirup S, Radutoiu S, Blaise M, Andersen KR, Menke FLH, Zipfel C, Stougaard J (2019). A Lotus japonicus cytoplasmic kinase connects Nod factor perception by the NFR5 LysM receptor to nodulation. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.1815425116
Open Access

Lead author is Jaslyn Wong. UK contribution from The Sainsbury Laboratory, University of East Anglia. This work was conducted in the legume Lotus and after a proteomic screen, the authors identified NFR5-interacting cytoplasmic kinase 4 that is involved in control of Nod factor perception.

Miller C, Wells R, McKenzie N, Trick M, Ball J, Fatihi A, Dubreucq B, Chardot T, Lepiniec L, Bevan MW (2019) Variation in expression of the HECT E3 ligase UPL3 modulates LEC2 levels, seed size and crop yield in Brassica napus. Plant Cell. doi: 10.1105/tpc.18.00577
Open Access

Lead author in Charlotte Miller. UK contribution from the John Innes Centre. Activity of the Brassica napus HECT E3 ligase gene BnaUPL3 controls seed weight per pod through degradation of LEC2, a master transcriptional regulator of seed maturation and reveals a potential target for crop improvement

Coudert Y, Novák O, Harrison CJ (2019) A KNOX-Cytokinin Regulatory Module Predates the Origin of Indeterminate Vascular Plants. Curr Biol. 2019 Aug 19;29(16):2743-2750.e5. doi: 10.1016/j.cub.2019.06.083

Lead author is Yoan Coudert. UK contribution from the University of Cambridge and University of Bristol. Class I KNOX gene activity is shown to be necessary for axis extension from an intercalary region of determinate moss shoots, in part through promotion of cytokinin biosynthesis.

Burgess SJ, Reyna-Llorens I, Stevenson SR, Singh P, Jaeger K, Hibberd JM (2019) Genome-wide transcription factor binding in leaves from C3 and C4 grasses Plant Cell.  doi: 10.1105/tpc.19.00078 Open Access

Lead author is Steven Burgess. UK contribution from University of Cambridge, The Sainsbury lab University of Cambridge, University of Leeds The authors use DNaseI-SEQ to assess the similarities and differences in transcription factor binding sites in the leaves across a set of four C3 and C4 grasses.

Harrington SA, Overend LE, Cobo N, Borrill P, Uauy C (2019) Conserved residues in the wheat (Triticum aestivum) NAM-A1 NAC domain are required for protein binding and when mutated lead to delayed peduncle and flag leaf senescence. BMC Plant Biol. doi: 10.1186/s12870-019-2022-
Lead author is Sophie Harrington. UK contributions from the John Innes Centre and University of Birmingham. The authors used a wheat TILLING resource to investigate mutrant allele with the NAC domain of the NAM-A1 transcription factor and their contribution to phenotypes in lab and field.

Jia Y, Burbidge CA, Sweetman C, Schutz E, Soole K, Jenkins C, Hancock RD, Bruning JB, Ford CM (2019) An aldo-keto reductase with 2-keto- L-gulonate reductase activity functions in L-tartaric acid biosynthesis from vitamin C in Vitis vinifera. J Biol Chem. doi: 10.1074/jbc.RA119.010196 Open Access

Lead author Yong Jia. UK contribution from the James Hutton Institute. This work conducted in grape reveals the mechanism by which an aldo-keto reductase functions in tartaric acid biosynthesis.

Perdomo JA, Degen GE, Worrall D, Carmo-Silva E (2019) Rubisco activation by wheat Rubisco activase isoform 2β is insensitive to inhibition by ADP. Biochem J. doi: 10.1042/BCJ2019011 Open Access

Lead author is Juan Alejandro Perdomo. UK contribution from Lancaster University. They show through analysis of site-directed mutations across three isoforms of wheat Rubisco activase that these isoforms have different sensitivities to ADP.

Gurrieri L, Distefano L, Pirone C, Horrer D, Seung D, Zaffagnini M, Rouhier N, Trost P, Santelia D, Sparla F (2019) The Thioredoxin-Regulated α-Amylase 3 of Arabidopsis thaliana Is a Target of S-Glutathionylation. Front Plant Sci. doi: 10.3389/fpls.2019.00993 Open Access

Lead author is Libero Gurrieri. UK contribution from John Innes Centre. The chloroplastic α-Amylases, AtAMY3 is post-translationally modified by S-glutathionylation in response to oxidative stress.

Mucha S, Heinzlmeir S, Kriechbaumer V, Strickland B, Kirchhelle C, Choudhary M, Kowalski N, Eichmann R, Hueckelhoven R, Grill E, Kuster B, Glawischnig E (2019) The formation of a camalexin-biosynthetic metabolon. Plant Cell. doi: 10.1105/tpc.19.00403 Open Access

Lead author is Stefanie Mucha. UK contribution from Oxford Brookes University and University of Warwick. The authors performed two independent untargeted co-immunoprecipitations to identify components involved in biosynthesis of the antifungal phytoalexin camalexin.

Atkinson N, Velanis CN, Wunder T, Clarke DJ, Mueller-Cajar O, McCormick AJ (2019) The pyrenoidal linker protein EPYC1 phase separates with hybrid Arabidopsis-Chlamydomonas Rubisco through interactions with the algal Rubisco small subunit. J Exp Bot. doi: 10.1093/jxb/erz275
Open Access

Lead author is Nicky Atkinson. UK contribution from the University of Edinburgh. This study uses Arabidopsis-Chlamydomonas to investigate the protein-protein interaction between Rubisco and essential pyrenoid component 1 (EPYC1).

Wightman R, Busse-Wicher M, Dupree P (2019) Correlative FLIM-confocal-Raman mapping applied to plant lignin composition and autofluorescence. Micron. doi: 10.1016/j.micron.2019.102733
Lead author Raymond Wightman. UK contribution from the Sainsbury Laboratory, University of Cambridge and the University of Cambridge. This study uses applies a novelmethod of correlative FLIM-confocal-Raman imaging to analyse lignin composition in Arabidopsis stems.

Milhinhos A, Vera-Sirera F, Blanco-Touriñán N, Mari-Carmona C, Carrió-Seguí À, Forment J, Champion C, Thamm A, Urbez C, Prescott H, Agustí J (2019) SOBIR1/EVR prevents precocious initiation of fiber differentiation during wood development through a mechanism involving BP and ERECTA. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.1807863116
Lead author is Ana Milhinho. UK contribution from the University of Oxford. The authors used GWAS in Arabidopsis to identify the SOBIR1/EVR as an important regulator of the control of secondary growth in xylem fibers.

Hartman S, Liu Z, van Veen H, Vicente J, Reinen E, Martopawiro S, Zhang H, van Dongen N, Bosman F, Bassel GW, Visser EJW, Bailey-Serres J, Theodoulou FL, Hebelstrup KH, Gibbs DJ, Holdsworth MJ, Sasidharan R, Voesenek LACJ (2019) Ethylene-mediated nitric oxide depletion pre-adapts plants to hypoxia stress. Nat Commun. doi: 10.1038/s41467-019-12045-4 Open Access

Lead author is Sjon Hartman. UK contribution from the University of Nottingham, Rothamsted Research and the University of Birmingham. This multinational collaboration looks into the relationship of how ethylene mediated nitric-oxide signaling responds to environmental signals.

Dittrich M, Mueller HM, Bauer H, Peirats-Llobet M, Rodriguez PL, Geilfus CM, Carpentier SC, Al Rasheid KAS, Kollist H, Merilo E, Herrmann J, Müller T, Ache P, Hetherington AM, Hedrich R (2019) The role of Arabidopsis ABA receptors from the PYR/PYL/RCAR family in stomatal acclimation and closure signal integration. Nat Plants. doi: 10.1038/s41477-019-0490-0
Lead author Marcus Dittrich. UK contribution from the University of Bristol. This work looks at the role of ABA signaling in stomatal responses and that the multiple ABA receptors can be modulated differentially in a stimulus-specific manner.

Villaécija-Aguilar JA, Hamon-Josse M, Carbonnel S, Kretschmar A, Schmid C, Dawid C, Bennett T, Gutjahr C (2019). SMAX1/SMXL2 regulate root and root hair development downstream of KAI2-mediated signalling in Arabidopsis. PLoS Genet. doi: 10.1371/journal.pgen.1008327 Open Access

Lead author Jose Antonio Villaécija-Aguilar. UK contribution from the University of Leeds and The Sainsbury lab, University of Cambridge. This demonstrates that KAI2 signalling through SMAX1/SMXL2 , is an important new regulator of root hair and root development in Arabidopsis.

GARNet Research Roundup: August 16th 2019

This holiday-time edition of the GARNet research roundup begins with two papers that include the late Ian Moore from the University of Oxford as a co-author. The first looks at the role of RAB-A5c in the control of cellular growth anisotropy whilst the second characterises the Transport Protein Particle II (TRAPPII) complex.

The third paper is a UK-wide collaboration that assesses the role of UVA signaling on stomatal development. Next is a paper from Cambridge and the JIC that has identified the TAF4b protein as a novel regulator of meiotic crossovers.

The fifth paper is from the University of York and characterizes a role for cis-12-oxo-phytodienoic acid (OPDA) during seed germination.

The next three papers feature scientists from the University of Leeds in research that investigates 1, a peroxisomal ABC transporter; 2, the role of LRR-RLKs in plasmodesmata development and 3, the cell wall characteristics of banana and mango fruit.

The ninth paper is from the University of Edinburgh and investigates the role of S-nitrosylation in the control of SUMO conjugation.

The next two papers include Steve Penfield at the JIC as a corresponding author; the first looks at the role of endosperm-expressed transcriptional factors during seed dormancy and the second, in collaboration with researchers at the University of Warwick, identifies novel QTLs involved in seed dormancy.

The penultimate study is from Lancaster and presents a surprising outcome resulting from the overexpression of the wheat CA1Pase gene. The final paper includes Alison Tidy and Zoe Wilson from University of Nottingham as co-authors on a study that looks at male fertility in Arabidopsis.

Kirchhelle C, Garcia-Gonzalez D, Irani NG, Jérusalem A, Moore I (2019) Two mechanisms regulate directional cell growth in Arabidopsis lateral roots. Elife. pii: e47988. doi: 10.7554/eLife.47988

Open Access

Charlotte Kirchhelle leads this work that was conducted in the lab of the late Ian Moore at the University of Oxford. She investigates the role of the plant-specific small GTPase RAB-A5c during growth anisotropy in lateral roots, which involves coordinated orientations of cellulose microfibrils (CMFs) and by cortical microtubules (CMTs). They identify RAB-A5c dependent and independent mechanisms to control cellular growth anisotropy in this growing tissue.


Kalde M, Elliott L, Ravikumar R, Rybak K, Altmann M, Klaeger S, Wiese C, Abele M, Al B, Kalbfuß N, Qi X, Steiner A, Meng C, Zheng H, Kuster B, Falter-Braun P, Ludwig C, Moore I, Assaad FF (2019) Interactions between Transport Protein Particle (TRAPP) complexes and Rab GTPases in Arabidopsis. Plant J. doi: 10.1111/tpj.14442

This German-led study includes Monika Kalde from the University of Oxford as first author as well Ian Moore as co-author. They characterize the components and function of the Transport Protein Particle II (TRAPPII) complex. TRAPPII plays multiple roles in intra-cellular transport and this study identified 13 subunits, including several that were previously uncharacterised.

Isner JC, Olteanu VA, Hetherington AJ, Coupel-Ledru A, Sun P, Pridgeon AJ, Jones GS, Oates M, Williams TA, Maathuis FJM, Kift R, Webb AR, Gough J, Franklin KA, Hetherington AM (2019). Short- and Long-Term Effects of UVA on Arabidopsis Are Mediated by a Novel cGMP Phosphodiesterase. Curr Biol.29(15):2580-2585.e4. doi: 10.1016/j.cub.2019.06.071

Open Access

Jean-Charles Isner is the first author on this collaboration between labs in Bristol, York, Oxford and Cambridge. They show that UVA radiation (which represents 95% of the UV radiation reaching earth) inhibits stomatal opening through a process that involves a reduction in the cytosolic level of cGMP. The AtCN-PDE1 gene (a cGMP-activated phosphodiesterase) is needed to decrease cGMP levels in Arabidopsis. This response is present across the tree of life except in metazoans. They show AtCN-PDE1 is needed for the UVA response and that prolonged UVA exposure causes increased growth yet reduced water use efficiency.

Lawrence EJ, Gao H, Tock AJ, Lambing C, Blackwell AR, Feng X, Henderson IR (2019) Natural Variation in TBP-ASSOCIATED FACTOR 4b Controls Meiotic Crossover and Germline Transcription in Arabidopsis. Curr Biol. pii: S0960-9822(19)30844-9. doi: 10.1016/j.cub.2019.06.084

Open Access

This work from Ian Henderson’s lab in Cambridge and Xiaoqi Feng’s lab at the JIC is led by Emma Lawrence and isolates a novel modifier of meiotic crossover frequency, TBP-ASSOCIATED FACTOR 4b (TAF4b), which encodes a subunit of the RNA polymerase II general transcription factor TFIID. They show TAF4b expression is enriched in meiocytes, compared to the more general expression of its paralog TAF4. Ultimately they reveal TAF4b drives a novel mode of meiotic recombination control through its activity as a general transcription factor.

Barros-Galvão T, Dave A, Cole A, Harvey D, Langer S, Larson TR, Vaistij FE, Graham IA (2019) cis-12-oxo-phytodienoic acid represses Arabidopsis thaliana seed germination in shade light conditions. J Exp Bot. pii: erz337. doi: 10.1093/jxb/erz337

Open Access

Thiago Barros-Galvão is first author on this study from Ian Graham’s lab at the University of York. They investigate how the jasmonic acid pre-cursor cis-12-oxo-phytodienoic acid (OPDA) contributes to control of seed germination, particularly under shade conditions. OPDA acts through the activity of the transcription factor MOTHER-OF-FT-AND-TFL1 (MFT).


Carrier DJ, van Roermund CWT, Schaedler TA, Rong HL, IJlst L, Wanders RJA, Baldwin SA, Waterham HR, Theodoulou FL, Baker A (2019) Mutagenesis separates ATPase and thioesterase activities of the peroxisomal ABC transporter, Comatose. Sci Rep. 9(1):10502. doi: 10.1038/s41598-019-46685-9

Open Access

Alison Baker at the University of Leeds is the corresponding author of this UK, Dutch collaboration that includes David Carrier as first author. They characterise the peroxisomal ABC transporter, Comatose (CTS) through mutagenesis of key residues responsible for the proteins intrinsic acyl-CoA thioesterase (ACOT) activity. Ultimately they show that ACOT activity depends of endogenous ATPase activity but that these activities could be functional separated by mutagenesis of key residues.

Grison M, Kirk P, Brault M, Wu XN, Schulze WX, Benitez-Alfonso Y, Immel F, Bayer EMF (2019). Plasma membrane-associated receptor like kinases relocalize to plasmodesmata in response to osmotic stress. Plant Physiol. pii: pp.00473.2019. doi: 10.1104/pp.19.00473

Open Access

GARNet advisory committee member Yoselin Benitez-Alfonso and members of her research group are co-authors on the next two studies. This work is led by Magali Grison in Emmanuelle Bayer’s lab in Bordeaux. They show that the PM-localised Leucine-Rich-Repeat Receptor-Like-Kinases (LRR-RLKs), QSK1 and IMK2 relocate and cluster to the plasmodesmata under osmotic stress conditions. Through a variety of assays that focuses on QSK1 the authors show that reorganisation of RLKs can be important for the regulation of callose deposition at plasmodesmata and under osmotic stress this can have a functional effect on lateral root development.

Rongkaumpan G, Amsbury S, Andablo-Reyes E, Linford H, Connell S, Knox JP, Sarkar A, Benitez-Alfonso Y, Orfila C (2019) Cell Wall Polymer Composition and Spatial Distribution in Ripe Banana and Mango Fruit: Implications for Cell Adhesion and Texture Perception. Front Plant Sci. 10:858. doi: 10.3389/fpls.2019.00858

Open Access

Ganittha Rongkaumpan is first author on this interdisciplinary collaborative research from multiple departments at the University of Leeds. They characterise the composition of the cell wall in two fruits, banana and mango, which soften during ripening. The authors compared structural information, obtained using Atomic Force Microscopy and biochemical analysis, with data from rheology and tribology assays to understand why these fruits feel different in the mouth during ingestion.

Skelly MJ, Malik SI, Le Bihan T, Bo Y, Jiang J, Spoel SH, Loake GJ (2019) A role for S-nitrosylation of the SUMO-conjugating enzyme SCE1 in plant immunity Proc Natl Acad Sci U S A. pii: 201900052. doi: 10.1073/pnas.1900052116

Michael Skelly from the University of Edinburgh is the lead author of this study from the labs of Gary Loake and GARNet chairman Steven Spoel. They investigate the mechanism through which nitric oxide signaling after pathogen recognition stimulates inhibitory S-nitrosylation of the Arabidopsis SUMO E2 enzyme, SCE1. S-nitrosylation occurs on the evolutionary conserved Cys139 of SCE1 and they investigate the wider significant of this residue in the control of immune responses across eukaryotes.

MacGregor DR, Zhang N, Iwasaki M, Chen M, Dave A, Lopez-Molina L, Penfield S (2019) ICE1 and ZOU determine the depth of primary seed dormancy in Arabidopsis independently of their role in endosperm development. Plant J. 98(2):277-290. doi: 10.1111/tpj.14211

Open Access

Dana MacGregor (now at Rothamsted Research) leads this work from the lab of Steve Penfield at the JIC that investigates the extent of control on depth of primary dormancy that is mediated by the endosperm-expressed transcription factors ZHOUPI (ZOU) and INDUCER OF CBF EXPRESSION1 (ICE1). These effects are additive and independent of their role in endosperm development since the dormancy defect in ice1 and zou mutants can be ameliorated without altering seed morphology. They show that ICE1 acts primarily through control of ABA INSENSITIVE 3 (ABI3).

Footitt S, Walley PG, Lynn JR, Hambidge AJ, Penfield S, Finch-Savage WE (2019) Trait analysis reveals DOG1 determines initial depth of seed dormancy, but not changes during dormancy cycling that result in seedling emergence timing. New Phytol. doi: 10.1111/nph.16081

This research is a collaboration between the John Innes Centre and the Universities Liverpool and Warwick, from which Steven Footitt is first author. They used two Arabidopsis ecotypes that have differences in the timing of seedling emergence to identify new QTLs involved in depth of seed dormancy and Seedling Emergence Timing (SET). They revealed that DOG1 is important for determining depth of dormancy. In addition they identified three new SET QTLs, which are each physically close to DOG1, that play a role in the control of SET in the field.

Lobo AKM, Orr D, Gutierrez MO, Andralojc J, Sparks C, Parry MAJ, Carmo-Silva E (2019) Overexpression of ca1pase decreases Rubisco abundance and grain yield in wheat. Plant Physiol. pii: pp.00693.2019. doi: 10.1104/pp.19.00693

Open Access

This research from Lancaster Environmental Centre and their Brazilian collaborators is led by Ana Karla Lobo and demonstrates that overexpression of 2-carboxy-D-arabinitol-1-phosphate phosphatase (CA1Pase) in wheat causes a reduction in above ground biomass and compromises wheat grain yields. As CA1Pase is involved in removing inhibitors of Rubisco activity this result is contrary to the anticipated outcome. This suggests that Rubisco inhibitors might actually protect enzyme activity, thus maintaining the number of active sites that the enzyme is able to support.

Zhao SQ, Li WC, Zhang Y, Tidy AC, Wilson ZA (2019) Knockdown of Arabidopsis ROOT UVB SENSITIVE4 Disrupts Anther Dehiscence by Suppressing Secondary Thickening in the Endothecium. Plant Cell Physiol. doi: 10.1093/pcp/pcz127

Shu-Qing Zhao is the lead author on this China-UK collaboration that includes Alison Tidy and Zoe Wilson from the University of Nottingham. They show that using an artificial microRNA to reduce levels of the RUS4 gene in Arabidopsis causes a decline in male fertility. They perform a detailed analysis of the RUS4 expression module and how it impacts fertility.

GARNet Research Roundup: July 26th 2019

This summer-time-reading bumper edition of the GARNet Research Roundup begins with two papers from the University of Sheffield that each use advanced imaging techniques. Firstly Andrew Fleming’s group leads a study on the link between stomatal function and mesophyll space morphology. Second is a study from Matthew Johnson’s group that looks at the dynamic arrangement of thylakoid stacks.

Next are two papers that include Alison Smith from the JIC as a corresponding author. The first also includes Vasilios Andriotis from the University of Newcastle and looks at the role of the plastidial pentose phosphate pathway during post-germination growth. Second uses a gene-editing strategy to generate potatoes with altered starch morphologies.

The fifth paper also looks at starch; researchers from Cambridge and Norwich are involved in a study that characterises the role of the LIKE SEX4 1 protein in starch degradation.

The sixth paper is from Aberystwyth University and identifies a transcription factor that alters secondary cell wall composition in Brachypodium and maize. Next is research from the University of Bath that looks at the role of a protein S-acyl transferase during seed germination.

The eighth and ninth papers are led by Spanish research groups and include contributions from UK-based co-authors in Cambridge and Nottingham, working on photoperiod perception or phosphate signaling respectively.

The tenth paper features work from Cardiff University and looks at the role of heterologous expression of the Arabidopsis WEE1 protein. The Bancroft lab from the University of York leads the next paper that investigates glucosinolate signaling in Brassica napus.

The final three manuscripts are methods papers. The first from Edinburgh introduces a new NanoLUC reporter whilst the other two include techniques involved in the investigation of light-regulated growth processes.

Lundgren MR, Mathers A, Baillie AL, Dunn J, Wilson MJ, Hunt L, Pajor R, Fradera-Soler M, Rolfe S, Osborne CP, Sturrock CJ, Gray JE, Mooney SJ, Fleming AJ (2019) Mesophyll porosity is modulated by the presence of functional stomata. Nat Commun. doi: 10.1038/s41467-019-10826-5

Open Access

This UK-wide study is led from Andrew Fleming’s lab in Sheffield and includes Marjorie Lundgren as first author (now working in Lancaster). They use microCT imaging alongside more traditional measurements linked to analysis of gas exchange to show that mesophyll airspace formation is linked to stomatal function in both Arabidopsis and wheat. This allows the authors to propose that coordination of stomata and mesophyll airspace pattern underpins water use efficiency in crops.

Wood WH, Barnett SFH, Flannery S, Hunter CN, Johnson MP (2019) Dynamic thylakoid stacking is regulated by LHCII phosphorylation but not its interaction with photosystem I. Plant Physiol. doi: 10.1104/pp.19.00503

Open Access

William Wood is the first author on this study from the University of Sheffield that uses 3D structured illumination microscopy (3D-SIM) to look at the dynamics of thylakoid stacking in both Arabidopsis and spinach. They show that the processes they observe are dependent on light harvesting complex II phosphorylation.

Andriotis VME, Smith AM (2019) The plastidial pentose phosphate pathway is essential for postglobular embryo development in Arabidopsis. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.1908556116

Open Access

Vasilios Andriotis (now at the University of Newcastle) is the lead author of this work performed in Alison Smith’s lab at the JIC. They look at the role of the plastidial oxidative pentose phosphate pathway (OPPP) during embryo development. This involved demonstrating that production of ribose-5-phosphate (R5P), which in turn leads to synthesis of purine nucleotides, is a critical function of the OPPP.

Tuncel A, Corbin KR, Ahn-Jarvis J, Harris S, Hawkins E, Smedley MA, Harwood W, Warren FJ, Patron NJ, Smith AM (2019) Cas9-mediated mutagenesis of potato starch-branching enzymes generates a range of tuber starch phenotypes. Plant Biotechnol J. doi: 10.1111/pbi.13137

Open Access

Alison Smith and Nicola Patron who work in Norwich Research Park are corresponding authors of this study that includes Aytug Tuncel as first author. They have used Cas9-mediated gene editing to generate potato plants that have a range of different tuber starch structures. This shows that gene-editing techniques allows the transgene-free alteration to generate potentially healthier crops.

Schreier TB, Umhang M, Lee SK, Lue WL, Shen Z, Silver D, Graf A, Müller A, Eicke S, Stadler M, Seung D, Bischof S, Briggs SP, Kötting O, Moorhead GB, Chen J, Zeeman SC (2019) LIKE SEX4 1 acts as a β-amylase-binding scaffold on starch granules during starch degradation. Plant Cell. doi: 10.1105/tpc.19.00089

Open Access

Tina Schreier from the University of Cambridge is the first author on this international study led from Switzerland that also includes Alexander Graf and David Seung from the JIC as co-authors. This study defines a precise role for the LIKE SEX FOUR 1 (LSF1) protein that binds starch and is required for normal starch degradation. Through a variety of experiments they show that the glucan binding, rather than phosphatase activity, is required for LSF1 function during starch degradation.

Bhatia R, Dalton S, Roberts LA, Moron-Garcia OM, Iacono R, Kosik O, Gallagher JA, Bosch M (2019) Modified expression of ZmMYB167 in Brachypodium distachyon and Zea mays leads to increased cell wall lignin and phenolic content. Sci Rep. doi: 10.1038/s41598-019-45225-9

Open Access

Rakesh Bhatia is the first author on this work from the lab of Maurice Bosch at Aberystwyth University. They overexpress the maize MYB transcription factor ZmMYB167 in both Brachypodium and maize. Both species show increased lignin content with Brachypodium but not maize showing a biomass deficit. This indicates that ZmMYB167 could be a useful molecular tool for the alteration of secondary cell wall biosynthesis.

Li Y, Xu J, Li G, Wan S, Batistic O, Sun M, Zhang Y, Scott R, Qi B (2019) Protein S-acyl Transferase 15 is Involved in Seed Triacylglycerol Catabolism during Early Seedling Growth in Arabidopsis (2019) J Exp Bot. doi: 10.1093/jxb/erz282

First author on this UK-Chinese collaboration is Yaxiao Li who works with Baoxiu Qi at the University of Bath. The authors characterise the function of Arabidopsis Protein Acyl Transferase 15, AtPAT15. This protein is involved in essential β-oxidation of triacylglycerols during post-germination growth.

Ramos-Sánchez JM, Triozzi PM, Alique D, Geng F, Gao M, Jaeger KE, Wigge PA, Allona I, Perales M (2019) LHY2 Integrates Night-Length Information to Determine Timing of Poplar Photoperiodic Growth. Curr Biol. doi: 10.1016/j.cub.2019.06.003

Open Access

This Spanish-led study includes co-authors from the Sainsbury Laboratory in Cambridge and attempts to define the factors that control photoperiod perception in trees, using poplar as a model system. FLOWERING LOCUS T2 (FT2) has been previously shown to be involved in this process and this study builds on that work to show that night-length information is transmitted by the clock gene LATE ELONGATED HYPOCOTYL 2 (LHY2) and is able to control FT2 expression.

Silva-Navas J, Conesa CM, Saez A, Navarro-Neila S, Garcia-Mina JM, Zamarreño AM, Baigorri R, Swarup R, Del Pozo JC (2019) Role of cis-zeatin in root responses to phosphate starvation. New Phytol. doi: 10.1111/nph.16020

Ranjan Swarup from the University of Nottingham is a co-author on this Spanish-led study that has Javier Silva-Navas as first author. Through analysis of dark-grown seedlings they have identified a set of new genes involved in root phosphate signaling. In addition they provide evidence of a links between cytokinin and phosphate signaling through modulation of the cell cycle.

Siciliano I, Lentz Grønlund A, Ševčíková H, Spadafora ND, Rafiei G, Francis D, Herbert RJ, Bitonti MB, Rogers HJ, Lipavská H (2019) Expression of Arabidopsis WEE1 in tobacco induces unexpected morphological and developmental changes. Sci Rep. 2019 Jun 18;9(1):8695. doi: 10.1038/s41598-019-45015-3

Open Access

Ilario Siciliano leads this work that includes colleagues from Hilary Rogers’ lab at Cardiff University. The WEE1 protein regulates the cell cycle across eukaryote lineages. In this work they show that overexpression of AtWEE1 in tobacco causes precocious flowering and increased shoot morphogenesis of stem explants whilst in cell culture this WEE1 OX causes smaller cell sizes.

Kittipol V, He Z, Wang L, Doheny-Adams T, Langer S, Bancroft I (2019) Genetic architecture of glucosinolate variation in Brassica napus. J Plant Physiol. doi: 10.1016/j.jplph.2019.06.001

Open Access

This study from the Bancroft lab at the University of York is led by Varanya Kittipol. Through use of Associative Transcriptomics (AT) across a diversity panel of 288 Brassica napus genotypes they are able to identify a set of genes involved in synthesis of glucosinate hydrolysis products.

Urquiza-García U, Millar AJ (2019). Expanding the bioluminescent reporter toolkit for plant science with NanoLUC. Plant Methods. doi: 10.1186/s13007-019-0454-4

Open Access

This study from the University of Edinburgh introduces NanoLUC, a new more stable luciferase-based reporter for use by the plant community.

The final two papers are methods papers that focus on different aspects of light-regulated growth. These are from the University of Southampton and University of York.

Terry MJ, Kacprzak SM (2019) A Simple Method for Quantification of Protochlorophyllide in Etiolated Arabidopsis Seedlings. Methods Mol Biol. doi: 10.1007/978-1-4939-9612-4_14

Oakenfull RJ, Ronald J, Davis SJ (2019) Measuring Phytochrome-Dependent Light Input to the Plant Circadian Clock. Methods Mol Biol. doi: 10.1007/978-1-4939-9612-4_15

GARNet Research Roundup: June 12th 2019

In another big edition of the GARNet Research Roundup we cover many different areas of research that utilise a varied group of experimental organisms!

The first paper from the Feng lab at the John Innes Centre performs an assessment of the factors influencing heterochromatin activity in sperm companion cells. Second is work from the JIC and Cardiff University that looks at the role of an auxin minima during fruit valve margin differentiation.

The next two papers have authors from Edinburgh. Firstly the McCormick lab has developed a stereo-based 3D imaging system for plants while Steven Spoel is a co-author on a study that looks at the pathogen responsive gene NPR1.

Coming from across the M8 is a paper from the Christie lab in Glasgow that looks into using phototropin genes as potential targets for crop improvement.

The next paper is from Oxford Brookes University where they visualise the movement of protein nanodomain clusters within the plasma membrane. Elsewhere in Oxford is a paper from the van der Hoorn group that characterises the effect of a novel triazine herbicide.

Two papers from the University of Durham also identify and characterise the role of novel herbicides, in this case on the activity of inositol phosphorylceramide synthases.

The final five papers feature research that each use different experimental organisms. Firstly a paper from the Earlham Institute uses delayed fluorescence to investigate the circadian clock in wheat and OSR. Second is a paper from Warwick that assesses the role of nodulation during nitrogen uptake in Medicago. The next paper features the Yant lab at University of Nottingham looks at growth of two species of Arabidopsis in challenging environments.

The penultimate paper includes authors from the University of Oxford and provides a detailed analysis of the factors controlling leaf shape in Cardamine and Arabidopsis thaliana. The final paper uses the imaging facility at the Hounsfield facility in Nottingham to image the roots of date palms.

He S, Vickers M, Zhang J, Feng X (2019) Natural depletion of H1 in sex cells causes DNA demethylation, heterochromatin decondensation and transposon activation. Elife. doi: 10.7554/eLife.42530

Open Access

Lead author on his paper is Shengbo He from Xiaoqi Feng’s lab at the John Innes Centre. This work looks at activation of Transposable elements (TEs) in the sperm companion cell of Arabidopsis. This is catalyzed by the DEMETER-catalyzed DNA demethylation in regions depleted of histone H1, demonstrating a key role for H1 in determining heterochromatin activity.

Li XR, Vroomans RMA, Fox S, Grieneisen VA, Østergaard L, Marée AFM (2019) Systems Biology Approach Pinpoints Minimum Requirements for Auxin Distribution during Fruit Opening. Mol Plant. doi: 10.1016/j.molp.2019.05.003

Open Access

Xin-Ran Li and Renske Vroomans are co-lead authors on this work from the Ostergaard, Grieneisen and Maree labs from the John Innes Centre and (now) Cardiff University.They look at the role of an auxin minima in the control of valve margin differentiation in Arabidopsis fruit. They used a cycle of experimental-modeling to develop a model that predicts the maturation of the auxin minimum to ensure timely fruit opening and seed dispersal.

Bernotas G, Scorza LCT, Hansen MF, Hales IJ, Halliday KJ, Smith LN, Smith ML, McCormick AJ (2019) A photometric stereo-based 3D imaging system using computer vision and deep learning for tracking plant growth. Gigascience. doi: 10.1093/gigascience/giz056

Open Access

Gytis Bernotas from UWE and Livia Scorza from the McCormick lab at the University of Edinburgh lead this work that is the result of a 2+ year collaboration with the Melvyn Smith and others at the Computer Machine Vision (CMV) facility at UWE. The authors have developed hardware and software (including a deep neural network) to automate the 3D imaging and segmentation of rosettes and individual leaves using a photometric stereo approach.

Chen J, Mohan R, Zhang Y, Li M, Chen H, Palmer IA, Chang M, Qi G, Spoel SH, Mengiste T, Wang D, Liu F, Fu ZQ (2019) NPR1 promotes its own and target gene expression in plant defense by recruiting CDK8. Plant Physiol. doi: 10.1104/pp.19.00124

GARNet chairman Steven Spoel is a co-author on this US-led study with Jian Chen as lead author. The paper investigates the interacting partners of NPR1 (NONEXPRESSER OF PR GENES 1), which is a master regulator of salicyclic signaling and therefore an important regulation of plant defense response.

Hart JE, Sullivan S, Hermanowicz P, Petersen J, Diaz-Ramos LA, Hoey DJ, Łabuz J, Christie JM (2019) Engineering the phototropin photocycle improves photoreceptor performance and plant biomass production. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.1902915116

Open Access

Jaynee Hart is first author on this research from Christie lab at the University of Glasgow in which they target the phototropin blue light receptor as a candidate for crop improvement. They showed plants that engineered to have a slow-photocycling version of PHOT1 or PHOT2 had increased biomass under low light conditions, due to their increased sensitivity to low light.

McKenna JF, Rolfe DJ, Webb SED, Tolmie AF, Botchway SW, Martin-Fernandez ML, Hawes C, Runions J (2019) The cell wall regulates dynamics and size of plasma-membrane nanodomains in Arabidopsis. Proc Natl Acad Sci U S A. doi: 10.1073/pnas.1819077116

Open Access

Joe McKenna from Oxford Brookes University leads this work that takes advantage of their superb imaging facilities to assess the dynamic regulation of specific protein clusters in the Arabidopsis plasma membrane. They show that the cytoskeleton (both actin and microtubule) and the cell wall play roles in the control of intra-PM moment of the pathogen receptor FLS2 and the auxin transporter PIN3.

Morimoto K, Cole KS, Kourelis J, Witt CH, Brown D, Krahn D, Stegmann M, Kaschani F, Kaiser M, Burton J, Mohammed S, Yamaguchi-Shinozaki K, Weerapana E, van der Hoorn RAL (2019) Triazine probes targeting ascorbate peroxidases in plants. Plant Physiol. doi: 10.1104/pp.19.00481

Open Access

Kyoko Morimoto is first author on this UK-German-Japanese collaboration led from the lab of GARNet committee member Renier van der Hoorn. They characterise the herbicidal effect of the small 1,3,5-triazine KSC-3 on ascorbate peroxidases (APXs) across a range of plant species.

Pinneh EC, Stoppel R, Knight H, Knight MR, Steel PG, Denny PW (2019) Expression levels of inositol phosphorylceramide synthase modulate plant responses to biotic and abiotic stress in Arabidopsis thaliana. PLoS One. doi: 10.1371/journal.pone.0217087

Open Access

Pinneh EC, Mina JG, Stark MJR, Lindell SD, Luemmen P, Knight MR, Steel PG, Denny PW (2019) The identification of small molecule inhibitors of the plant inositol phosphorylceramide synthase which demonstrate herbicidal activity. Sci Rep. doi: 10.1038/s41598-019-44544-1

Open Access

Elizabeth Pinneh leads these two papers from the Denny lab in Durham. In the first paper they use RNAseq data and analysis of overexpression transgenic lines to define the role of inositol phosphorylceramide synthase (IPCS) during abiotic and biotic stress responses.

Secondly they screened a panel of 11000 compounds for their activity against the AtIPCS2 in a yeast two-hybrid assay. Successful hits from the screen were confirmed with in vitro enzyme assays and in planta against Arabidopsis.

Rees H, Duncan S, Gould P, Wells R, Greenwood M, Brabbs T, Hall A (2019) A high-throughput delayed fluorescence method reveals underlying differences in the control of circadian rhythms in Triticum aestivum and Brassica napus. Plant Methods. doi: 10.1186/s13007-019-0436-6

Open Access

Hannah Rees from Anthony Hall’s lab at the Earlham Institute leads this methods paper that introduces the use of delayed fluorescence to investigate the circadian rhythms in wheat and oil seed rape.

Lagunas B, Achom M, Bonyadi-Pour R, Pardal AJ, Richmond BL, Sergaki C, Vázquez S, Schäfer P, Ott S, Hammond J, Gifford ML (2019) Regulation of Resource Partitioning Coordinates Nitrogen and Rhizobia Responses and Autoregulation of Nodulation in Medicago truncatula. Mol Plant. doi: 10.1016/j.molp.2019.03.014

Open Access

Beatriz Lagunas is lead author on this paper from the University of Warwick that investigates the role of nodulation in actual nitrogen uptake by the roots of Medicago truncatula. They use integrated molecular and phenotypic analysis to determine that the respond to nitrogen flux are processed on a whole plant level through multiple developmental processes.

Preite V, Sailer C, Syllwasschy L, Bray S, Ahmadi H, Krämer U, Yant L (2019) Convergent evolution in Arabidopsis halleri and Arabidopsis arenosa on calamine metalliferous soils Philos Trans R Soc Lond B Biol Sci. doi: 10.1098/rstb.2018.0243

Open Access

Veronica Preite is first author on this UK-German collaboration led by Ute Kraemer and Levi Yant in Nottingham. They performed whole genome resequenced of 64 individuals of two Arabidopsis species that grow on calamine metalliferous sites (which have toxic levels of the zinc and cadmium). They revealed a modest amount of gene and network convergence in plants that have colonised these challenging environments.

Kierzkowski D, Runions A, Vuolo F, Strauss S, Lymbouridou R, Routier-Kierzkowska AL, Wilson-Sánchez D, Jenke H, Galinha C, Mosca G, Zhang Z, Canales C, Dello Ioio R, Huijser P, Smith RS, Tsiantis M (2019) A Growth-Based Framework for Leaf Shape Development and Diversity. doi: 10.1016/j.cell.2019.05.011

Open Access

Claudia Canales and Carla Galinha from Oxford are co-authors on this German-led study from Miltos Tsiantis’ lab that performs a detailed dissection of the growth parameters that control differences in leaf-shape in Cardamine and Arabidopsis. They show critical roles for the SHOOTMERISTEMLESS and REDUCED COMPLEXITY homeobox proteins to define differences in shape determination.

Xiao T, Raygoza AA, Pérez JC, Kirschner G, Deng Y, Atkinson B, Sturrock C, Lube V, Wang JY, Lubineau G, Al-Babili S, Ramírez LAC, Bennett MJ, Blilou I (2019) Emergent Protective Organogenesis in Date Palms: A Morpho-devo-dynamic Adaptive Strategy During Early Development. Plant Cell. doi: 10.1105/tpc.19.00008

Open Access

Members of the Hounsfield CT Imaging Facility 
at the University of Nottingham are co-authors on this paper that is led by Tingting Xiao from KAUST in Saudi Arabia. The paper takes a detailed look at root morphology in Date Palm.

GARNet Research Roundup: April 29th 2019

This edition of the GARNet research roundup features fundamental plant science research conducted in a range of experimental organisms. Firstly Liam Dolan’s lab in Oxford looks at the function of bHLHs proteins in cell differentiation across land plant evolution. Secondly Anthony Hall’s group at the Earlham Institute have identified a novel RecQ helicase involved in work exclusively conducted in wheat. Thirdly researchers from Nottingham work with Arabidopsis to characterise an EXPANSIN protein essential for lateral root development.

The fourth paper is the first of two that look at germination and uses a new model, Aethionema arabicum, to study the role of light in seed dormancy. This work includes research from Royal Holloway. The second ‘dormancy’ paper is from Peter Eastmond’s lab at Rothamsted and further characterises the DOG1 gene in Arabidopsis. The penultimate paper includes co-authors from Warwick and Leeds and introduces a novel chemical inhibitor of auxin transport. The final paper from researchers in Birmingham introduces the 3DCellAtlas Meristem, a powerful tool for cellular annotation of the shoot apical meristem.

Bonnot C, Hetherington AJ, Champion C, Breuninger H, Kelly S, Dolan L (2019) Neofunctionalisation of basic helix loop helix proteins occurred when embryophytes colonised the land. New Phytol. doi: 10.1111/nph.15829

Clemence Bonnot is lead author on this study from Liam Dolan’s lab at the University of Oxford in which the authors assess the role of ROOT HAIR DEFECTIVE SIX-LIKE (RSL) genes during evolution of plant development. They look at the function of a member of this bHLH transcription factor family called CbbHLHVIII identified in the charophyceaen alga Chara braunii. This gene is expressed at specific morphologically important regions in the algae and cannot rescue the function of related RSL genes in Marchantia or Arabidopsis. This suggests that the function of RSL proteins in cell differentiation has evolved by neofunctionalisation through land plant lineages.

Gardiner LJ, Wingen LU, Bailey P, Joynson R, Brabbs T, Wright J, Higgins JD, Hall N, Griffiths S, Clavijo BJ, Hall A (2019) Analysis of the recombination landscape of hexaploid bread wheat reveals genes controlling recombination and gene conversion frequency. Genome Biol. 20(1):69. doi: 10.1186/s13059-019-1675-6

Open Access

Laura Gardiner and Anthony Hall lead this work that was conducted at the Earlham Institute and uses a bespoke set of bioinformatic tools that allow fundamental questions to be asked in hexaploid wheat. They looked at crossover and gene conversion frequencies in 13 recombinant inbred mapping populations and were able to identity an important QTL and confirm functionality for a novel RecQ helicase gene. This gene does not exist in Arabidopsis and therefore this discovery-motivated research needed to be conducted in wheat. They hope that this identification will provide future opportunities to tackle the challenge of linkage drag when attempting to develop new crops varieties.

Ramakrishna P, Ruiz Duarte P, Rance GA, Schubert M, Vordermaier V, Vu LD, Murphy E, Vilches Barro A, Swarup K, Moirangthem K, Jørgensen B, van de Cotte B, Goh T, Lin Z, Voβ U, Beeckman T, Bennett MJ, Gevaert K, Maizel A, De Smet I (2019) EXPANSIN A1-mediated radial swelling of pericycle cells positions anticlinal cell divisions during lateral root initiation. Proc Natl Acad Sci U S A. 2019 Apr 3. pii: 201820882. doi: 10.1073/pnas.1820882116

Open Access

This pan-European study is led by Priya Ramakrishna at the University of Nottingham and includes co-authors from the UK, Belgium, Germany and Denmark. The authors look at the lateral root development and characterise the function of the EXPANSIN A1 protein. This protein influences the physical changes in the cell wall that are needed to enable the asymmetry cell divisions that define the location of a new lateral root. Plants lacking EXPA1 function do not properly form lateral roots and are unable to correctly respond to an inductive auxin signal. This clearly demonstrates an important requirement for the activity of genes that transmit cell signals into the physical relationships that exist between cells.

Mérai Z, Graeber K, Wilhelmsson P, Ullrich KK, Arshad W, Grosche C, Tarkowská D, Turečková V, Strnad M, Rensing SA, Leubner-Metzger G, Scheid OM (2019) Aethionema arabicum: a novel model plant to study the light control of seed germination. J Exp Bot. pii: erz146. doi: 10.1093/jxb/erz146

Open Access

This paper includes authors from the UK, Germany, Austria and the Czech Republic including Kai Graeber and Gerhard Leubner-Metzger at Royal Holloway. They introduce the Brassica Aethionema arabicum as a new model to investigate the mechanism of germination inhibition by light as they have identified accessions that are either light-sensitive or light-neutral. In contrast germination in Arabidopsis is stimulated by light. Transcriptome analysis of Aethionema arabicum accessions reveal expression changes in key hormone-regulated genes. Overall they show that largely the same module of molecular components are involved in control of of seed dormancy irrespective of the effect of light on germination. Therefore any phenotypic changes likely result from changes in the activity organisms-specific of these genes.

Bryant FM, Hughes D, Hassani-Pak K, Eastmond PJ (2019) Basic LEUCINE ZIPPER TRANSCRIPTION FACTOR 67 transactivates DELAY OF GERMINATION 1 to establish primary seed dormancy in Arabidopsis. Plant Cell. pii: tpc.00892.2018. doi: 10.1105/tpc.18.00892

Open Access

Fiona Bryant is lead author on this research from Rothamsted Research that investigates the factors that control expression of the DOG1 gene, which is a key regulator of seed dormancy. They show that LEUCINE ZIPPER TRANSCRIPTION FACTOR67 (bZIP67) regulates DOG1 expression and have uncovered a mechanism that describes the temperature-dependent regulation of DOG1 expression. Finally they identity a molecular change that explains known allelic difference in DOG1 function, which informs different levels of dormancy in different accessions.

Oochi A, Hajny J, Fukui K, Nakao Y, Gallei M, Quareshy M, Takahashi K, Kinoshita T, Harborough SR, Kepinski S, Kasahara H, Napier RM, Friml J, Hayashi KI (2019) Pinstatic acid promotes auxin transport by inhibiting PIN internalization. Plant Physiol. 2019 Apr 1. pii: pp.00201.2019. doi: 10.1104/pp.19.00201

Open Access

This Japanese-led study includes co-authors from the Universities of Warwick and Leeds and describes the identification of a novel positive chemical modulator of auxin cellular efflux. This aptly named PInStatic Acid (PISA) prevents PIN protein internalization yet does not impact the SCFTIR1/AFB signaling cascade. Therefore the authors hope that PISA will be a useful tool for unpicking the cellular mechanisms that control auxin transport.

Montenegro-Johnson T, Strauss S, Jackson MDB, Walker L, Smith RS, Bassel GW. (2019) 3D Cell Atlas Meristem: a tool for the global cellular annotation of shoot apical meristems. Plant Methods. 15:33. doi: 10.1186/s13007-019-0413-0

Open Access

Thomas Montenegro-Johnson, Soeren Strauss, Matthew Jackson and Liam Walker lead this methods paper that was prepared following research that took place at the University of Birmingham and the Max Planck Institute for Plant Breeding Research in Cologne. They describe the 3DCellAtlas Meristem, a tool allows the complete cellular annotation of cells within a shoot apical meristem (SAM), which they have successfully tested in both Arabidopsis and tomato. The authors state that ‘this provides a rapid and robust means to perform comprehensive cellular annotation of SAMs and digital single cell analyses, including cell geometry and gene expression’.

GARNet Research Roundup: March 7th 2019

This edition of the GARNet research roundup begins with a study into the genetic basis of fertility in barley led by Sarah McKim from Dundee. Second is a study from Oxford and Leicester that characterizes the proteolytic control of chloroplast import. The third paper from Levi Yant’s group at JIC and Nottingham that attempts to discover the influence of polyploidism on population genomic effects whilst the fourth paper from Juliet Coates’ lab in Birmingham uses the growth of Arabidopsis to assess the potential of algal biomass as a biofertiliser. The next two papers include co-authors from Oxford and Warwick respectively and investigate different factors that control seed viability in Arabidopsis and Brassica oleracea. The final paper includes Seth Davies from York as a co-author on a study that looks at control of the circadian clock in field-grown Arabidopsis.

Zwirek M, Waugh R, McKim SM (2019) Interaction between row-type genes in barley controls meristem determinacy and reveals novel routes to improved grain. New Phytol. doi: 10.1111/nph.15548

Open Access

Current GARNet committee members Sarah McKim is the leader of this study in which first author is Monica Zwirek. They investigate the mechanism through which the barley VRS genes contribute to spikelet fertility. They undercover the epistatic relationship between five VRS genes that explains how they contribute to controlling fertility of lateral spikelets. Importantly they demonstrate that various vrs mutant combinations improve fertility in a variety of ways, information that will be useful during the generation of new varieties of barley.

Ling Q, Broad W, Trösch R, Töpel M, Demiral Sert T, Lymperopoulos P, Baldwin A, Jarvis RP (2019) Ubiquitin-dependent chloroplast-associated protein degradation in plants. Science. doi: 10.1126/science.aav4467

Qihua Ling and William Broad are the first authors on this study from the Universities of Oxford and Leicester. They investigate the role of proteolysis in the functional control of chloroplast-envelope translocases, which are required for the transport of proteins from nucleus-encoded genes into the chloroplast. They identify two newly characterised proteins that function in the same pathway as the known ubiquitin E3 ligase SP1. These novel proteins, SP2 and CDC48, are both required for the movement of ubiquitinated proteins from the chloroplast outer envelope membrane (OEM) into the cytosol, where they are degraded by the proteolytic machinery. This process of chloroplast-associated protein degradation (CHLORAD) maintains tight control of the activity of OEM proteins and is essential for organelle function.

Monnahan P, Kolář F, Baduel P, Sailer C, Koch J, Horvath R, Laenen B, Schmickl R, Paajanen P, Šrámková G, Bohutínská M, Arnold B, Weisman CM, Marhold K, Slotte T, Bomblies K, Yant L (2019) Pervasive population genomic consequences of genome duplication in Arabidopsis arenosa. Nat Ecol Evol. doi: 10.1038/s41559-019-0807-4.

Patrick Monnahan at the John Innes Centre is first author on this study from the Yant lab that has recently moved to the University of Nottingham. In this collaboration with colleagues in the US, Austria, Sweden, the Czech Republic and Slovakia, they have performed large scale sequencing on 39 populations of Arabidopsis arenosa. These plants have differing levels of ploidy and they are attempting to understand how ploidy effects population genomics. They demonstrate that the ploidy effects are subtle but significant and that masking of deleterious mutations, faster substitution rates and interploidy introgression will likely impact the evolution of populations where polyploidy is common.

Ghaderiardakani F, Collas E, Damiano DK, Tagg K, Graham NS, Coates J (2019) Effects of green seaweed extract on Arabidopsis early development suggest roles for hormone signalling in plant responses to algal fertilisers. Sci Rep. doi: 10.1038/s41598-018-38093-2

Open Access

This work from the Coates lab at the University of Birmingham is led by Fatemeh Ghaderiardakani and looked into the potential of algal extracts as biofertiliser. They showed that at >0.1%, extracts taken from the common green seaweed Ulva intestinalis inhibit Arabidopsis seed germination and root elongation. At lower concentrations primary root elongation was promoted albeit with a complete loss of lateral root formation. Elemental analysis allows the authors to suggest that this effect was mediated via a novel mechanism involving aluminium. Overall the authors caution against the use of algal biofertilisers due to potential unforeseen negative effects on plant growth.

Viñegra de la Torre N, Kaschani F, Kaiser M, van der Hoorn RAL, Soppe WJJ, Misas Villamil JC (2019) Dynamic hydrolase labelling as a marker for seed quality in Arabidopsis seeds. Biochem J. doi: 10.1042/BCJ20180911.

GARNet Committee member Renier van der Hoorn is a co-author on this German-led study that investigates how the activity of seed-localised proteases can affect Arabidopsis seed germination. This study has clear real-world application regarding the storage of economically important seed stocks. They show that vacuolar processing enzymes (VPEs) become more active during aging whilst the activity of serine hydrolases declines alongside seed quality. This information has allowed the authors to develop protease-activity-based markers that will provide information about seed quality.

Schausberger C, Roach T, Stöggl WM, Arc E, Finch-Savage WE, Kranner I (2019) Abscisic acid-determined seed vigour differences do not influence redox regulation during ageing. Biochem J. doi: 10.1042/BCJ20180903

William Finch-Savage from the University of Warwick is a co-author on this Austrian-led study that looks at the effect of aging on the quality of Brassica oleracea seeds stored at two oxygen concentrations. Higher O2 causes a more rapid decrease in seed quality through aging yet in contrast aging did not alter the impact of the hormone ABA on seed viability. This study enables the authors to uncover two mechanisms that control seed quality that appear to act through different mechanisms.

Rubin MJ, Brock MT, Davis SJ, Weinig C (2019) QTL Underlying Circadian Clock Parameters Under Seasonally Variable Field Settings in Arabidopsis thaliana G3 (Bethesda). doi: 10.1534/g3.118.200770

Open Access

Seth Davies from the University of York is a co-author on this study led by Matthew Rubin from the University of Wyoming. They looked at the growth of Arabidopsis thaliana recombinant inbred lines grown in field conditions and found an extremely nuanced relationship regarding how QTLs that influence the circadian clock respond to environmental conditions. For example the authors showed that plant growth in June, July and September is controlled by different QTL architecture, demonstrating the complex regulation of the circadian clock in these field growth plants.

«page 1 of 4

Follow Me
July 2020

Welcome , today is Monday, July 13, 2020