GARNet Research Roundup: June 4th

This weeks GARNet Research Roundup begins with a paper from researchers at the University of Dundee, James Hutton Institute, Durham University and the University of Glasgow that characterises a functional role for alternative splicing during the cold response. Second is a paper from Newcastle University that investigates the role of the OXI1 kinase during aphid predation. Third is a paper that includes University of Bristol co-authors that looks at strigolactone signaling in moss whilst the fourth paper from researchers at Leeds and QMUL studies the role of ascorbate during photosynthesis. The final paper from Warwick and York uses gene expression data from pathogen-infected plants to generate a model for predicting a strategy for synthetic engineering of the defence response.


Calixto CPG, Guo W, James AB, Tzioutziou NA, Entizne JC, Panter PE, Knight H, Nimmo H, Zhang R, Brown JWS (2018) Rapid and dynamic alternative splicing impacts the Arabidopsis cold response transcriptome. Plant Cell doi: 10.1105/tpc.18.00177.

www.plantcell.org/content/early/2018/05/15/tpc.18.00177.long

Open Access

Cristiane Calixto and Wenbin Guo work with John Brown at University of Dundee and the James Hutton Institute and in this large-scale biology paper they characterise the role of alternative splicing (AS) during a stress response. RNAseq was performed on plants exposed to cold stress and they showed that hundreds of genes undergo AS just a few hours after temperature decrease and that this response is sensitive to small changes. The authors propose that AS is a mechanism to fine-tune changes in thermo-plasticity of gene expression and in addition they investigate the activity of the novel splicing factor U2B”-LIKE.

Christiane will discuss this research at the upcoming GARNet2018 meeting held at the University of York in September 2018.


Shoala T, Edwards MG, Knight MR, Gatehouse AMR. OXI1 kinase plays a key role in resistance of Arabidopsis towards aphids (Myzus persicae) (2018) Transgenic Res. doi: 10.1007/s11248-018-0078-x.

Open Access

This work is led by Tahsin Shoala in the lab of Angharad Gatehouse at Newcastle University and demonstrates a novel role for MAPK cascades in resistance to aphid predation. They investigate mutants in OXI1 kinase, a gene that activates MAPK signaling and demonstrate a reduction in the aphid population build-up. Furthermore they show that the effect of OXI works through a mechanism that involves callose deposition, demonstrated as oxi1 mutants lack the upregulation of a set of β-1,3-glucanase genes following predation.


Lopez-Obando M, de Villiers R, Hoffmann B, Ma L, de Saint Germain A, Kossmann J, Coudert Y, Harrison CJ, Rameau C, Hills P, Bonhomme S (2018) Physcomitrella patens MAX2 characterization suggests an ancient role for this F-box protein in photomorphogenesis rather than strigolactone signalling. New Phytol. doi: 10.1111/nph.15214

GARNet committee member Jill Harrison is a co-author on this paper that is led by Mauricio Lopez‐Obando working at Université Paris-Saclay. In Physcomitrella patens development they investigate the role of the moss ortholog of the Arabidopsis strigolactone signaling mutant MAX2. Previous work had shown that moss does response to SL signaing but they find that although Ppmax2 mutants showed defects in early development and photomorphogenesis they do not show changes in the SL response. Fascinatingly this indicates that the molecular components that control SL signaling have diverged in vascular plants and seemingly co-opted a role for MAX2 that was previously not required in mosses.


https://academic.oup.com/jxb/article/69/11/2823/4991886

Plumb W, Townsend AJ, Rasool B, Alomrani S, Razak N, Karpinska B, Ruban AV, Foyer CH. Ascorbate-mediated regulation of growth, photoprotection and photoinhibition in Arabidopsis thaliana (2018) J Exp Bot. doi: 10.1093/jxb/ery170

William Plumb (Leeds) and Alexandra Townsend (QMUL) are the lead authors on this study that investigates the importance of ascorbate during photosynthesis. In this work they analysed the growth of ascorbate synthesis mutants that are smaller and have less biomass than wildtype plants. However these plants have normal levels of non-photoinhibiton, allowing the authors to conclude that ascorbate is needed for growth but not photoprotection.


Foo M, Gherman I, Zhang P, Bates DG, Denby K (2018) A Framework for Engineering Stress Resilient Plants using Genetic Feedback Control and Regulatory Network Rewiring. ACS Synth Biol. doi: 10.1021/acssynbio.8b00037
Mathias Foo and Iulia Gherman (University of Warwick) are lead authors on work that analyses gene expression data taken from Botrytis cinerea-infected Arabidopsis. They have identified a network of genes involved in the defence response. They validate their model against previously obtained time series data and then perturb the model in two differences ways, focused on the transcription factor CHE. This analysis demonstrates the potential of combining feedback control theory with synthetic engineering in order to generate plants that are resistant to biotic stress.

https://pubs.acs.org/doi/10.1021/acssynbio.8b00037

GARNet Research Roundup: April 11th 2018

This weeks GARNet research roundup begins with a microscopy-based study led by Lorenzo Frigerio from the University of Warwick that investigates the origin of Protein Storage Vacuoles. The second paper from John Doonan at Aberystwyth University looks at how differential splicing of cyclin-dependent Kinase G1 effects the thermosensory response. Reiner van de Hoorn from Oxford leads the next paper that characterises the use of activity-based protein profiling (ABPP) to identify novel α-glycosidases in model and non-model plants. Simon McQueen-Mason from York is corresponding author of the next paper that identified a new QTL from Brachypodium that is involved in cell wall formation. The fifth paper is led by Anthony Dodd from Bristol and characterises the role of the SnRK1 complex in hypocotyl elongation whilst the penultimate manuscript from Julia Davies’s lab in Cambridge performs patch clamp analysis of dorn1 mutant plants. The final paper from Brendan Davies at the University of Leeds characterises the SMG kinase, a gene that is lacking from the Arabidopsis genome, in Physcomitrella patens.


http://www.plantphysiol.org/content/early/2018/03/19/pp.18.00010.long

Feeney M, Kittelmann M, Menassa R, Hawes C, Frigerio L. Protein storage vacuoles originate from remodelled pre-existing vacuoles in Arabidopsis thaliana (2018) Plant Physiol. 2018 Mar 19. pii: pp.00010.2018. doi: 10.1104/pp.18.00010 Open Access

This collaboration between the Universities of Warwick and Oxford Brookes is led by Lorenzo Frigerio and Chris Hawes. They have investigated the origin of seed Protein Storage Vacuoles (PSV) using a two-pronged approach using confocal and immunoelectron microscopy. They looked at embryo development as well as in leaf cells that have been reprogrammed for embryonic cell fate by overexpression of the LEAFY COTYLEDON2 TF. These studies indicate that PSVs are formed following the reprogramming of pre-existing embryonic vacuole (EV) rather than from de novo assembly.


https://onlinelibrary.wiley.com/doi/abs/10.1111/tpj.13914

Cavallari N, Nibau C, Fuchs A, Dadarou D, Barta A, Doonan JH. The Cyclin Dependent Kinase G group defines a thermo-sensitive alternative splicing circuit modulating the expression of Arabidopsis ATU2AF65A (2018) Plant J. doi: 10.1111/tpj.13914 Open Access

John Doonan (Aberystwyth University) is the corresponding author on this UK-Austrian collaboration that presents the role of the cyclin-dependent Kinase G1 (CDKG1) in thermosensing in Arabidopsis. Ambient temperature change causes altered gene expression of the spliceosome component, ATU2AF65A. Interestingly the CDKG1 gene is differentially spliced and to produces two protein isoforms that are both needed to complement the expression of ATU2AF65A across a temperature range. This alternative splicing is dependent on CDKG2 and CYCLIN L1 and is a novel control mechanism in the temperature control response.


Husaini AM, Morimoto K, Chandrasekar B, Kelly S, Kaschani F, Palmero D, Jiang J, Kaiser M, Ahrazem O, Overkleeft HS, van der Hoorn RAL (2018) Multiplex fluorescent, activity-based protein profiling identifies active α-glycosidases and other hydrolases in plants. Plant Physiol. pii: pp.00250.2018. doi: 10.1104/pp.18.00250 Open Access

Renier Van de Hoorn (University of Oxford) leads this pan-european study that uses novel cyclophellitol aziridine probes that label α-glycosidase enzymes. They identified two novel α-glycosidases in Arabidopsis as well as using the technique in non-model saffron crocus. Finally they showed that this multiplex fluorescent labelling in combination with probes for serine hydrolases and cysteine proteases can be used to identify changes in hydrolase activity in response to pathogen infection.


Whitehead C, Ostos Garrido FJ, Reymond M, Simister R, Distelfeld A, Atienza SG, Piston F, Gomez LD, McQueen-Mason SJ (2018) A glycosyl transferase family 43 protein involved in xylan biosynthesis is associated with straw digestibility in Brachypodium distachyon. New Phytol. doi: 10.1111/nph.15089 Open Access

Simon McQueen-Mason (University of York) leads this study that use QTL mapping to identify a gene in Bracypodium that is involved in cell wall architecture, which might then be a target to develop plants with improved cellulose digestibility. This glycosyl transferase family (GT) 43 protein is an orthologue of Arabidopsis IRX14, which is involved in xylan biosynthesis. When RNAi was used to reduce expression of this gene the resulting plants showed increased digestibility, indicating that this BdGT43A will be a good target for future breeding plans.


Wang L, Wilkins KA, Davies JM (2018) Arabidopsis DORN1 extracellular ATP receptor; activation of plasma membrane K(+) -and Ca(2+) -permeable conductances New Phytol. 2018 Mar 25. doi: 10.1111/nph.15111. Open Access

This letter to New Phytologist from the lab of Julia Davis (University of Cambridge) outlines some experiments to determine whether the DORN1 plasma membrane receptor is responsible for transmitting a signal from extracellular ATP (eATP). They performed patch clamp analysis on isolated protoplasts and showed that DORN1 is involved in the activation of Ca+ and K+ pumps by eATP as, in contrast to wildtype, dorn1 mutant protoplast showed no voltage changes after incubation with eATP.


Simon NML, Sawkins E, Dodd AN. Involvement of the SnRK1 subunit KIN10 in sucrose-induced hypocotyl elongation (2018) Plant Signal Behav. 27:1-9. doi: 10.1080/15592324.2018.1457913.

Anthony Dodd (University of Bristol) is the corresponding author of this follow-on study from one that previously featured on the GARNet YouTube channel. This study measures sucrose-induced hypocotyl elongation in two T-DNA mutants of the SnRK1 subunit KIN10 gene. These mutants had altered responses to sucrose leading to the hypothesis that the SnRK1 complex suppresses hypocotyl elongation in the presence of external sugar.


Lloyd JPB, Lang D, Zimmer AD, Causier B, Reski R, Davies B (2018) The loss of SMG1 causes defects in quality control pathways in Physcomitrella patens. Nucleic Acids Res. doi: 10.1093/nar/gky225 Open Access

Brendan Davis (University of Leeds) is the corresponding author on research that investigates the role of the SMG1 kinase during nonsense-mediated mRNA decay (NMD) in the moss Physcomitrella patens. This kinase plays a critical role in animals but as it is not present in Arabidopsis, its function is not well studied in plants. However moss smg mutants show expression changes in genes involved in a variety of processes indicating that NMD is a common control mechanism in moss. In addition these plants have increased susceptibility to DNA damage, which suggests that the SMG1 kinase is a key player in quality control mechanisms in plants.

https://academic.oup.com/nar/advance-article/doi/10.1093/nar/gky225/4955258

Arabidopsis Research Roundup: March 9th

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Published on: March 9, 2018

This Arabidopsis Research Roundup has five papers that includes two from the John Innes Centre and two from the University of Edinburgh. Firstly Kristen Bomblies’s group at the JIC have investigated the relationship between temperature and meiotic recombination rates. Secondly Veronica Grieneisen and Stan Maree have developed a mathematical model to characterise cell morphologies taken from a 2D image. Andrew Miller from Edinburgh is a co-corresponding author on a study that shows how the Arabidopsis proteome changes in different photoperiods. In the fourth paper Peter Doerner is a co-author on work that looks at the phosphate starvation response. Finally researchers from Bristol and Nottingham contribute to an investigation into a novel genetic component that controls auxin-induced root hair development.


Lloyd A, Morgan C, Franklin C, Bomblies K (2018) Plasticity of Meiotic Recombination Rates in Response to Temperature in Arabidopsis. Genetics. doi: 10.1534/genetics.117.300588

Open Access

Kristen Bomblies (John Innes Centre) leads this study that investigates the influence of temperature on meiotic recombination rate. They show that in Arabidopsis the number of crossovers positively correlates with increasing temperature. However the mechanistic explanation for the increase at higher temperatures remains opaque as, in contrast to findings from other plants, synaptonemal complex length negatively correlates with temperature.


Sánchez-Corrales YE, Hartley M, van Rooij J, Marée AFM, Grieneisen VA (2018) Morphometrics of complex cell shapes: Lobe Contribution Elliptic Fourier Analysis (LOCO-EFA). Development. doi: 10.1242/dev.15677

http://dev.biologists.org/content/early/2018/02/08/dev.156778.long

Open Access

Veronica Grieneisen and Stan Maree (John Innes Centre) lead this study that has developed the Lobe Contribution Elliptical Fourier Analysis (LOCO-EFA) method. This generates meaningful descriptors from a 2D image of cells that can then be linked to morphological features. This tool allows for the efficient phenotyping of cell morphologies that they demonstrate by analysing images of Arabidopsis leaf pavement cells. They extend this analysis to larger populations where they used LOCO-EFA to predict how cell shapes change when they move into a more crowded space.


Seaton DD, Graf A, Baerenfaller K, Stitt M, Millar AJ, Gruissem W (2018) Photoperiodic control of the Arabidopsis proteome reveals a translational coincidence mechanism. Mol Syst Biol. doi: 10.15252/msb.20177962 Open Access

http://onlinelibrary.wiley.com/doi/10.15252/msb.20177962/abstract

Andrew Miller (University of Edinburgh) is the corresponding author on this collaboration with German and Swiss colleagues that compares the Arabidopsis proteome across four photoperiods. They shows coordinated changes across the proteome, most notably at longer photoperiods in the abundance of proteins involved in photosynthesis and metabolism. They show higher translation rates during the day that correspond with the increased RNA abundance that is a characteristic of circadian rhythms. This ‘translational coincidence’ describes the alignment of higher translation rates with high transcript levels and they assigned a mathematical model in an attempt to explain this phenomenon.


Hanchi M, Thibaud MC, Légeret B, Kuwata K, Pochon N, Beisson F, Cao A, Cuyas L, David P, Doerner P, Ferjani A, Lai F, Li-Beisson Y, Mutterer J, Philibert M, Raghothama KG, Rivasseau C, Secco D, Whelan J, Nussaume L, Javot H (2018) The phosphate fast-responsive genes PECP1 and PPsPase1 affect phosphocholine and phosphoethanolamine content. Plant Physiol. doi: 10.1104/pp.17.01246 Open Access

Peter Doerner (University of Edinburgh) is a co-author on this global study that characterises the phosphate starvation-mediated induction of the HAD-type phosphatases PPsPase1 (AT1G73010) and PECP1 (AT1G17710). They show that expression of these genes closely follows phosphate status but that their activity does not alter phospate content. The role of these proteins is to control phosphocholine and phosphoethanolamine content, which is a output of changing phosphate conditions. The authors conclude that expression of these genes can be an excellent molecular marker for the phosphate starvation response.


www.cell.com/current-biology/fulltext/S0960-9822(18)30083-6

Schoenaers S, Balcerowicz D, Breen G, Hill K, Zdanio M, Mouille G, Holman TJ, Oh J, Wilson MH, Nikonorova N, Vu LD, De Smet I, Swarup R, De Vos WH, Pintelon I, Adriaensen D, Grierson C, Bennett MJ, Vissenberg K (2018) The Auxin-Regulated CrRLK1L Kinase ERULUS Controls Cell Wall Composition during Root Hair Tip Growth. Current Biology doi: 10.1016/j.cub.2018.01.050

This Belgian-led study includes contributions from Claire Greirson’s and Malcolm Bennett’s labs in Bristol and Nottingham respectively. They investigate the role of the ERULUS (ERU) protein, an auxin-induced receptor-like kinase, during the development of root hairs. ERU localises to the apical root hair plasma membrane and regulates cell wall composition by altering pectin dynamic. The authors conclude that ERU is a key regulator of auxin-mediated control of root hair development.

Arabidopsis Research Roundup: January 23rd.

This weeks Arabidopsis Research Roundup begins with two papers from Royal Hollaway University of London that investigate the factors that control leaf development in the dark and the control of PIN1 phosphorylation. Third is a paper from Bristol that demonstrates the translation of research from Arabidopsis into coriander with regard the control of the response to UV light. Next is research from the John Innes Centre that characterises the role of DNA methylation during meiosis in the male lineage.

Christine Foyer (Leeds) leads the next paper that defines the relationship between cold treatment and strigolactone signalling. The penultimate paper is led by Richard Napier from the University of Warwick and determines the parameters that define the substrates of the AUX1 protein whilst the final paper includes Cyril Zipfel (TSL) as a co-author and uses systems biology approaches to characterise the interactions between leucine-rich repeat receptor kinases (LRR-RKs).


Mohammed B, Farahi Bilooei S, Doczi R, Grove E, Railo S, Palme K, Ditengou FA, Bögre L, Lopez-Juez E (2017) Converging energy and hormonal signalling control meristem activity, leaf initiation and growth Plant Phys doi: 10.1104/pp.17.01730

http://www.plantphysiol.org/content/early/2017/12/28/pp.17.01730.long

Open Access

Enrique Lopez-Juez (RHUL) leads this collaboration with German and Hungarian colleagues that investigates the fundamental question; ‘Why don’t leaves grow in the dark’. They show that this response is influenced by both auxin transport and the plants energy sensing mechanisms. Interestingly when energy is provided via external sucrose, leaves develop differently in the dark than they do in the light indicating that multiple signaling pathways differentially influence this phenotype.

Enrique discusses this paper on the GARNet YouTube page.


Dory M, Hatzimasoura E, Kállai BM, Nagy SK, Jäger K, Darula Z, Nádai TV, Mészáros T, López-Juez E, Barnabás B, Palme K,,, Bögre L, Ditengou FA,,, Dóczi R (2017) Coevolving MAPK and PID phosphosites indicate an ancient environmental control of PIN auxin transporters in land plants. FEBS Lett. doi: 10.1002/1873-3468.12929

Laszlo Bogre and Enrique Lopez-Juez (RHUL) are co-authors on this Hungarian-led study that has discovered 3 conserved putative MAPK sites within the auxin transport protein PIN1. Phosphorylation of two of these sites causes partial loss of PIN1 membrane localization and therefore opposes the effect of the PINOID kinase, whose activity promotes PIN1 membrane localisation.


https://www.nature.com/articles/s41598-017-18073-8

Fraser DP, Sharma A, Fletcher T, Budge S, Moncrieff C, Dodd AN, Franklin KA (2017) UV-B antagonises shade avoidance and increases levels of the flavonoid quercetin in coriander (Coriandrum sativum). Sci Rep. doi: 10.1038/s41598-017-18073-8 Open Access

Keara Franklin and Anthony Dodd (University of Bristol) lead this collaboration between academic researchers and those in the company Vitacress. They translate research from Arabidopsis into Coriander that looks at the effect of UV-B on stem elongation and the interaction with flavonoid signaling. This work shows that alterations to the UV-B regime during growth of potted herbs might reduce deleterious effects caused by neighbour proximity.


Walker J, Gao H, Zhang J, Aldridge B, Vickers M, Higgins JD, Feng X (2017) Sexual-lineage-specific DNA methylation regulates meiosis in Arabidopsis. Nat Genet. doi: 10.1038/s41588-017-0008-5

Xiaoqi Feng (JIC) is the corresponding author on this collaboration with James Higgins from Leicester and they investigate the role of DNA methylation in the control of male meiosis. They demonstrate that RNA-directed DNA methylation (RdDM) in the male lineage regulates gene expression in meiocytes and results in the mis-splicing of the MPS1/PRD2 transcipt, which causes aberrant alterations in spindle formation.


Cooper JW, Hu Y, Beyyoudh L, Yildiz Dasgan H, Kunert K, Beveridge CA, Foyer CH (2018) Strigolactones positively regulate chilling tolerance in pea and in Arabidopsis. Plant Cell Environ. doi: 10.1111/pce.13147

Christine Foyer (Leeds) is the corresponding author on this collaboration with Australian, Turkish and South African colleagues that looks into the role strigolactones play during chilling tolerance in both Arabidopsis and pea plants. Plants that have been chilled during the night have reduced biomass, which was not observed in either pea or Arabidopsis strigolactone mutants. This demonstrates a clear role for this hormone in this response and provides a potential target for the manipulation of plant growth under environmental conditions.


Hoyerova K, Hosek P, Quareshy M, Li J, Klima P, Kubes M,, Yemm AA, Neve P, Tripathi A, Bennett MJ, Napier RM (2017) Auxin molecular field maps define AUX1 selectivity: many auxin herbicides are not substrates. New Phytol. doi: 10.1111/nph.14950

onlinelibrary.wiley.com/doi/10.1111/nph.14950/abstract

Together with Czech co-authors Richard Napier (Warwick University) leads this investigation into the mode of action of the AUX1 auxin influx carrier and its substrate preferences. This work made use of a novel auxin accumulation assay and associated mathematical modeling to describe the parameters that make difference auxins to be good candidates for the AUX1 transport. Interesting they find that many commonly used auxinicide herbicides are poor substrates for AUX1 and the relevance of this finding for herbicide management strategies.


https://www.nature.com/articles/nature25184

Smakowska-Luzan E et al (2018) An extracellular network of Arabidopsis leucine-rich repeat receptor kinases. Nature doi: 10.1038/nature25184

Cyril Zipfel (TSL) is a co-author on this US-European study that performs a systems-biology analysis on the possible interactions between extracellular domains of the leucine-rich repeat receptor kinases (LRR-RKs) gene family in Arabidopsis. Analysis of 40K potential interactions allows the generation of a LRR-based cell surface interaction network (CSI-LRR). This was used to discover previously uncharacterized interactions between LRR-RKs and to demonstrate that these interactions allow the translocation of extracellular signals in balanced and tightly regulated patterns.

Arabidopsis Research Roundup: January 10th 2018

This Arabidopsis Research Roundup covers the final papers of 2017 and the first of this new year. The initial paper is led by researchers in Bristol and characterises how the multifaceted BIG protein influences stomatal dynamics in response to altered CO2. Second is a manuscript from SLCU that for the first time in plants demonstrates nuclear sequestration of cell cycle regulated mRNAs.

Next is a paper from Rothamsted that describes a role for the hormone GA during floral development. David Salt (Nottingham) is then a co-author on a manuscript that has determined a role for the CTL protein in ion homeostasis.

Seth Davies from York is the lead author on the next study that investigates a link between metabolism and the circadian clock. The sixth paper looks at genes involved in the control of autophagy and features Patrick Gallois (Manchester) as a co-author.

There are three papers from researchers working on Norwich Research Park with Cyril Zipfel (TSL) involved in a study that looks at vacuolar trafficking of BR signaling components. Janneke Balk leads a study that characterises enzymes involved in biosynthesis of metal co-factors whilst the final NRP-based paper from Nick Pullen and Steven Penfield (John Innes Centre) describes the Leaf-GP open software for automated plant phenotyping.

The penultimate paper uses a set of PlantProbes (developed by Paul Knox at Leeds) to study pollen development whilst the final paper from Keith Lindsey (Durham) describes the application of a Bayesian statistical methodology to model the parameters that control a hormone signaling network.


He J, Zhang RX, Peng K, Tagliavia C, Li S, Xue S, Liu A, Hu H,, Zhang J, Hubbard KE,, Held K, McAinsh MR, Gray JE, Kudla J, Schroeder JI, Liang YK, Hetherington AM (2018) The BIG protein distinguishes the process of CO2 -induced stomatal closure from the inhibition of stomatal opening by CO2. New Phytol. doi: 10.1111/nph.14957 Open Access

Alistair Hetherington (University of Bristol) leads this UK-USA-China collaboration that has characterised a role for the mysterious BIG protein during stomatal closure in response to altered CO2 concentration. Interestingly BIG mutants do not show a defect in stomatal opening in response to altered CO2, allowing the dissection of this complex response through the activity of this protein. It remains to be determined exactly how the BIG protein influences this process.


Yang W, Wightman R, Meyerowitz EM (2017) Cell Cycle Control by Nuclear Sequestration of CDC20 and CDH1 mRNA in Plant Stem Cells. Mol Cell. doi: 10.1016/j.molcel.2017.11.008

Elliott Meyerowitz (SLCU) is the corresponding author of this research that provides the first characterisation in plants of nuclear sequestration of mRNAs from developmental important genes. The authors show that Arabidopsis anaphase-promoting complex/cyclosome (APC/C) coactivator genes CDC20 and CCS52B are confined to the nucleus in prophase, preventing translation of the cognate proteins until metaphase, which appears to protect cyclins from degradation at an inappropriate phase of the cell cycle


Plackett ARG, Powers SJ, Phillips AL, Wilson ZA, Hedden P, Thomas SG4 (2017) The early inflorescence of Arabidopsis thaliana demonstrates positional effects in floral organ growth and meristem patterning. Plant Reprod. doi: 10.1007/s00497-017-0320-3

This study is led from Rothamsted Research and includes Zoe Wilson from the University of Nottingham. They perform a systematic analysis of early floral organ initiation across the Arabidopsis inflorescence, discovering that both GA-dependent and independent stages are important for this process, albeit via the activity of presently unknown factors.


Gao YQ, Chen JG, Chen ZR An D, Lv QY, Han ML, Wang YL, Salt DE, Chao DY (2017) A new vesicle trafficking regulator CTL1 plays a crucial role in ion homeostasis. PLoS Biol. doi: 10.1371/journal.pbio.2002978

Open Access

David Salt (University of Nottingham) is a co-author on this Chinese-led investigation into the role of the vesicle trafficking regulator choline transporter (CTL) during the control of ionome homeostasis. Using ctl1 mutants they show that this function is required for the action of certain ion transporters as well as during plasmodesmata (PD) development. This study provides novel insights into the role of vesicular transport in the control of ion homeostasis and how the location of these ions might alter vesicle activity.


Sánchez-Villarreal A, Davis AM, Davis SJ (2017) AKIN10 Activity as a Cellular Link Between Metabolism and Circadian-Clock Entrainment in Arabidopsis thaliana.

Plant Signal Behav. doi: 10.1080/15592324.2017.1411448

Seth Davies (University of York) is the corresponding author on this study demonstrating that overexpression of the AKIN10 subunit of the SnRK1 complex results in increased period length of the circadian clock. The authors postulate about the possible links between metabolic rate and function of the clock, allowing them to present a model of action that features each of the central regulatory elements.


Havé M, Balliau T, Cottyn-Boitte B, Dérond E, Cueff G, Soulay F, Lornac A, Reichman P, Dissmeyer N, Avice JC, Gallois P, Rajjou L, Zivy M, Masclaux-Daubresse C (2017) Increase of proteasome and papain-like cysteine protease activities in autophagy mutants: backup compensatory effect or pro cell-death effect? J Exp Bot. doi: 10.1093/jxb/erx482

Open Access
This study is led by French researchers and includes Patrick Gallois (University of Manchester) as a co-author. The work focuses on the role of the ATG genes during autophagy, the key process that controls nutrient recycling during senescence. In atg5 mutants they show that different sets of proteases are misregulated, suggestive of a complex relationship between the enzymes involved in nutrient remobilization.


Liu Q, Vain T, Viotti C, Doyle SM, Tarkowská D, Novák O, Zipfel C, Sitbon F, Robert S, Hofius D (2017) Vacuole Integrity Maintained by DUF300 Proteins Is Required for Brassinosteroid Signaling Regulation. Mol Plant. doi: 10.1016/j.molp.2017.12.015

Cyril Zipfel (TSL) is a member of this Pan-European consortium that investigates the role of the vacuolar proteins, LAZARUS1 (LAZ1) and LAZ1 HOMOLOG1 (LAZ1H1) on the cellular cycling of BR-signaling components. Plants with mutations in laz1 and laz1h1 show increased BAK1 accumulation at the tonoplast as well as enhanced BRI1 trafficking and degradation. These DUF300 proteins appear to play a specific role in BR signalling as other vacuolar-associated proteins are not involved in this process.


Kruse I, Maclean A, Hill L, Balk J (2017) Genetic dissection of cyclic pyranopterin monophosphate biosynthesis in plant mitochondria. Biochem J. doi: 10.1042/BCJ20170559 Open Access

Janneke Balk (John Innes Centre) leads this study that has identified novel alleles in mitochondrial enzymes that are involved in the biosynthesis of metal cofactors. Analysis of these enzyme mutant reveals that they show deficiencies in the synthesis of cyclic pyranopterin monophosphate (cPMP), revealing fresh insights into the metabolic processes involving this key intermediate.


Zhou J, Applegate C, Alonso AD, Reynolds D, Orford S, Mackiewicz M, Griffiths S, Penfield S, Pullen N (2017) Leaf-GP: an open and automated software application for measuring growth phenotypes for arabidopsis and wheat. Plant Methods. doi: 10.1186/s13007-017-0266-3

Open Access

Nick Pullen and Steve Penfield (John Innes Centre) introduce this new software tool for the automated measurement of plant phenotypes. This Leaf-GP software is open access and has the sophistication to discriminate between different aspects of both Arabidopsis and greenhouse growth wheat.

This paper is back of a special issue of Plant Methods that is based on the use of Computer Vision in Plant Phenotyping.


Ndinyanka Fabrice T, Vogler H, Draeger C, Munglani G, Gupta S, Herger AG, Knox JP, Grossniklaus U, Ringli C (2017) LRX Proteins play a crucial role in pollen grain and pollen tube cell wall development. Plant Physiol. doi: 10.1104/pp.17.01374

Open Access

This Swiss-led study looks into the role of LRX proteins during cell wall formation and how they affect pollen germination and pollen tube formation. The authors took advantage of the molecular tools produced by Paul Knox (University of Leeds) as part of his Plant Probes project.


Vernon I, Liu J, Goldstein M, Rowe J, Topping J, Lindsey K (2017) Bayesian uncertainty analysis for complex systems biology models: emulation, global parameter searches and evaluation of gene functions. BMC Syst Biol. doi: 10.1186/s12918-017-0484-3 Open Access

Keith Lindsey (University of Durham) leads this paper that applies a Bayesian statistical methodology to analyse a model of hormonal crosstalk in the Arabidopsis root. They show that this technique can provide new insight into the behavior of models and enables the identification of new interesting rate parameters.

Arabidopsis Research Roundup: Nov 24th

The week’s UK Arabidopsis research roundup includes seven papers from groups who work on a range of topics.

Firstly Antony Dodd (Bristol) investigates the role of sugar signaling during hypocotyl elongation and provides an audio description of this groups work. Secondly Mike Holdsworth (Nottingham) leads a paper that demonstrates the importance of the N-rule pathway in the response to abiotic stresses. Thirdly are a set of papers that have developed models on three different topics. Mike Blatt’s group at Glasgow University has a cross-scale model that is applied to stomatal opening whilst Stan Maree and Veronica Griensien (JIC) use modeling to predict how the topology of pavement cells is determined. Finally Arabidopsis is used as an example that fits a model that investigates how critical mutation rate (CMR) changes with population size. In the sixth paper Lorraine Williams and colleagues (University of Southampton) investigate the function of a rice transport protein involved in manganese tolerance by expressing it in Arabidopsis. The final paper from Jerzy Paszkowski (SLCU) outlines a novel screening strategy for retrotransposons and the identification of an ecotype specific element.


Simon NM, Kusakina J, Fernández-López Á, Chembath A, Belbin FE, Dodd AN (2017) The energy-signalling hub SnRK1 is important for sucrose-induced hypocotyl elongation. Plant Physiol. doi: 10.1104/pp.17.01395

Open Access

This UK-wide collaboration is led by Anthony Dodd at the University of Bristol and has looked at the factors that control hypocotyl elongation in response to sugar signalling. This response is integrated through the sugar-signalling hub, SnRK1 and is regulated by trehalose-6-phosphate (Tre6P). They also integrate hormone signalling and the influence of diurnal rhythms into the control of this process, importantly showing that the ubiquitous sugar regulator hexokinase is not involved in this process.

Antony kindly provides an audio description of this research that can be found on YouTube or on the GARNet iTunes channel. Please subscribe!


Vicente J, Mendiondo GM, Movahedi M, Peirats-Llobet M, Juan YT, Shen YY, Dambire C, Smart K, Rodriguez PL, Charng YY, Gray JE, Holdsworth MJ (2017) The Cys-Arg/N-End Rule Pathway Is a General Sensor of Abiotic Stress in Flowering Plants. Current Biology doi: 10.1016/j.cub.2017.09.006

Open Access

Mike Holdsworth (University of Nottingham) is the corresponding author of this collaboration with colleagues from Sheffield, Spain and Taiwan that investigates how the N-rule degradation pathway acts a sensor of general abiotic stress in both Arabidopsis and Barley. These responses are integrated through degradation of the group VII Ethylene Response Factor transcription factors (ERFVIIs) family via direct and indirect pathways. In addition they link ERFVII activity with chromatin-remodeling ATPase BRAHMA providing evidence for a single mechanism that links the responses to a number of environmental signals.


Wang Y, Hills A, Vialet-Chabrand SR, Papanatsiou M, Griffiths H, Rogers S, Lawson T, Lew V, Blatt MR (2017) Unexpected Connections between Humidity and Ion Transport Discovered using a Model to Bridge Guard Cell-to-Leaf Scales. Plant Cell. doi: 10.1105/tpc.17.00694

Open Access

Mike Blatt (University of Glasgow) leads this collaboration with researchers at the Universities of Cambridge and Essex. They have developed the OnGuard2 quantitative systems platform that integrates numerous parameters that control guard cell dynamics across many scales including at molecular, cellular, tissue and canopy levels. They experimentally demonstrate that OnGuard2 faithfully reproduces the kinetics of real stomatal movement and therefore that this modeling is able to bridge the micro-macro divide.


Carter R, Sánchez-Corrales YE, Hartley M, Grieneisen VA, Marée AFM (2017) Pavement cells and the topology puzzle. Development. doi: 10.1242/dev.157073

Stan Maree and Veronica Griensien (John Innes Centre) lead this study that has looked at the patterning of 50000 Arabidopsis pavement cells to understand the topological signatures that exist in this population. They have developed a heuristic cellular division rule to produce a model that can reproduce their observations by predicting how these cells divide. They confirmed their model by tracking 800 mitotic events, allowing them to conclude that distinct topology is not a direct consequence of the jigsaw-like shape of the cells, but rather owes itself to life-history-driven process, with limited impact from cell surface mechanics.


Aston E, Channon A, Belavkin RV, Gifford DR, Krašovec R, Knight CG (2017) Critical Mutation Rate has an Exponential Dependence on Population Size for Eukaryotic-length Genomes with Crossover. Sci Rep. doi: 10.1038/s41598-017-14628-x

Open Access

In this study a team of computational biologists from Keele, Middlesex and Manchester have used Arabidopsis as an exemplar to understand how critical mutation rate (CMR) provides insights into the shift between survival-of-the-fittest and survival of individuals with greater mutational robustness. They have produced a simulation for these parameters that predicts outcomes for a range of biological organisms, showing that CMR decreases with reduced population size. They suggest that the model can be used to understand the conservation strategies exhibited in populations that are approaching extinction.


Farthing EC, Menguer PK, Fett JP, Williams LE (2017) OsMTP11 is localised at the Golgi and contributes to Mn tolerance. Sci Rep. doi: 10.1038/s41598-017-15324-6
Lorraine Williams (University of Southampton) and her colleagues have identified a transporter protein from rice, OsMTP11 that is involved in mangenase tolerance. They show that heterologous expression of this protein is able to rescue the manganese sensitive phenotype of Arabidopsis mtp11-3 knockouts. They show that OsMTP11 localises to the Golgi and have also conducted site directed mutagenesis to identify key residues that are important for the function of this protein.


Griffiths J, Catoni M, Iwasaki M, Paszkowski J (2017) Sequence-independent identification of active LTR retrotransposons in Arabidopsis. Mol Plant. doi: 10.1016/j.molp.2017.10.012

Open Access

Jerzy Paszkowski (SLCU) leads this single-figure short manuscript that has characterised the population of retrotransposons in Arabidopsis. They develop a novel cost-effective screening strategy that allows them to identify sequences found on extrachromosomal DNA (ecDNA), which includes a retroelement found in Lansberg erecta but not in the reference genome ecotype Col-0.

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