The first GARNet Research Roundup of 2020 begins with a study from the University of Dundee at the James Hutton Institute in which they have adapted nanopore direct sequencing to analyse the Arabidopsis mRNA methylome. The second study is also from Dundee and is an analysis of alternative splicing in C4 sugarcane.
The next two papers look at the control of stomatal development. In the first, researchers from Bristol investigate the integration of temperature and light-induced signals whilst the second paper is from Sheffield and looks at the role, or lack thereof, of the HY5 protein. The fifth paper is also from Sheffield and looks at the role of the MALECTIN DOMAIN KINESIN 2 protein in dividing tissues.
The next two papers investigate the control of lateral root formation. Firstly researchers from Glasgow look at how potassium signaling integrates with both the mechanisms of RNA-directed DNA-methylation and the auxin response. The other paper looks at how auxin signaling integrates with the plasmodesmata development and includes co-authors from the University of Nottingham.
The eighth paper is led from Nottingham and looks at the role of the PROTEOLYSIS (PRT)1 during the plant immune response whilst the next paper, which is from the University of Cambridge, also looks at plant immunity, specifically at how the biosynthesis of phytic acid impacts this response.
The remaining four papers include UK-based co-authors from University of South Wales, Rothamsted and Cardiff, Durham, Oxford and Aberystwyth in international research teams led from Malaysian (the expression of Acyl-CoA-binding proteins in oil palm), China (the effect of silver nanoparticles on plant growth), Japan (convergent evolution of lateral organ formation) and Chile (the factors that influence grain filling in wheat) respectively.
Parker MT, Knop K, Sherwood AV, Schurch NJ, Mackinnon K, Gould PD, Hall AJ, Barton GJ, Simpson GG (2020) Nanopore direct RNA sequencing maps the complexity of Arabidopsis mRNA processing and m(6)A modification. Elife. doi: 10.7554/eLife.49658 Open Access
Matt Parker, Kasia Knop, Anya Sherwood and Nicholas Schurch are co-first authors on this study from the University of Dundee at the James Hutton Institute in which they perform direct RNA sequencing using a nanopore sequencer. They used this technical advance to analyse the mRNA (m6A) methylome and reveal a contribution to the control of the circadian clock. Future use of this technique will undoubtedly allow for an improved annotation of the Arabidopsis genome (and others).
Dantas LLB, Calixto CPG, Dourado MM, Carneiro MS, Brown JWS, Hotta CT (2019) Alternative Splicing of Circadian Clock Genes Correlates With Temperature in Field-Grown Sugarcane. Front Plant Sci. doi: 10.3389/fpls.2019.01614 Open Access
This study is led from Brazil with Luiza Dantas as first author and includes co-authors from the University of Dundee at the James Hutton Institute. They investigate the level of alternative splicing (AS) in commercial sugarcane, which is an important C4 crop. Tissue samples were collected in winter and summer and this analysis reveals temperature- and organ-dependent differences in the levels of AS across a set of genes under circadian control.
Kostaki KI, Coupel-Ledru A, Bonnell VC, Gustavsson M, Sun P, Mclaughlin FJ, Fraser DP, McLachlan DH, Hetherington AM, Dodd AN, Franklin KA (2020). Guard cells integrate light and temperature signals to control stomatal aperture. Plant Physiol. doi: 10.1104/pp.19.01528 Open Access
Kalliopi-Ioanna Kostaki is first author on this study from the University of Bristol that begins to unpick the mechanisms that integrate light and temperature signals in the control of stomatal development. These signals converge on phototropin photoreceptors and multiple members of the 14-3-3 protein family. This work also reveals a currently uncharacterised pathway that controls temperature regulation of guard cell movement.
Zoulias N, Brown J, Rowe J, Casson SA (2020) HY5 is not integral to light mediated stomatal development in Arabidopsis. PLoS One. doi: 10.1371/journal.pone.0222480 Open Access
Nick Zoulias is first author on this study from the Casson lab at University of Sheffield. ELONGATED HYPOCOTYL 5 (HY5) is a key regulator of light-mediated development yet in this study the authors show that the HY5-signaling cascade does not play a role in stomatal development. This key finding shows that phytochrome and cryptochrome signaling in guard cells is transmitted via non-HY5 signaling components.
Galindo-Trigo S, Grand TM, Voigt CA, Smith LM (2020) A malectin domain kinesin functions in pollen and seed development in Arabidopsis. J Exp Bot doi: 10.1093/jxb/eraa023
This research from the Smith lab at
the University of Sheffield is led by Sergio Galindo-Trigo. They show
that MALECTIN DOMAIN KINESIN 2 (MDKIN2) is involved in pollen, embryo
and endosperm development. Malectin domains bind polysaccharides and
peptides when found extracellularly in receptor-like kinases so this
might suggest that in dividing tissues MDKIN2 plays a role during the
physical division of cells.
Shahzad Z, Eaglesfield R, Carr C, Amtmann A (2020) Cryptic variation in RNA-directed DNA-methylation controls lateral root development when auxin signalling is perturbed. Nat Commun. doi: 10.1038/s41467-019-13927-3 Open Access
Zaigham Shahzad at the University of Glasgow is the first author in this study that looks at the relationship between potassium deficiency and lateral root formation. This effect is mediated via the impact of CLSY1, a key component of the RNA-directed DNA-methylation machinery, on the transcriptional repression of the AuxIAA protein IAA27. Interestingly this system appears to act as a backup to the auxin-dependent proteolysis pathway that is primarily responsible for the control of IAA27 activity.
Sager R, Wang X, Hill K, Yoo BC, Caplan J, Nedo A, Tran T, Bennett MJ, Lee JY (2020) Auxin-dependent control of a plasmodesmal regulator creates a negative feedback loop modulating lateral root emergence. Nat Commun. doi: 10.1038/s41467-019-14226-7.
This US study is led by Ross Sager and includes co-authors from the University of Nottingham. This research links the role of auxin in lateral root formation with plasmodesmata development through control of the plasmodesmal regulator PDLP5. They present a model wherein molecules required for lateral root emergence transit through plasmodesmata following an inductive auxin signal.
Till CJ, Vicente J, Zhang H, Oszvald M, Deery MJ, Pastor V, Lilley KS, Ray RV, Theodoulou FL, Holdsworth MJ (2019) The Arabidopsis thaliana N-recognin E3 ligase PROTEOLYSIS1 influences the immune response. Plant Direct. doi: 10.1002/pld3.194 Open Access
Christopher Till, Jorge Vicente and Hongtao Zhangis are co-first authors on this research led from the University of Nottingham and Rothamsted Research that involves use of quantitative proteomics to define the role of the N-recognin E3 ligase PROTEOLYSIS (PRT)1 during the plant immune response.
Poon JSY, Le Fevre RE, Carr JP, Hanke DE, Murphy AM (2019)
Inositol hexakisphosphate biosynthesis underpins PAMP-triggered
immunity to Pseudomonas syringae pv. tomato in Arabidopsis thaliana but
is dispensable for establishment of systemic acquired resistance. Mol Plant Pathol. doi: 10.1111/mpp.12902
This research from the University of Cambridge is led by Jacquelyne Poon and Alex Murphy
and looks at the role of the phytic acid (inositol hexakisphosphate,
InsP6) biosynthesis in dividing tissues during the plant immune
response. They characterize Arabidopsis plants with mutations in
biosynthetic enzymes to show that there are multiple mechanisms of basal
resistance that are dependent upon InsP6.
Amiruddin N, Chan PL,
Azizi N, Morris PE, Chan KL, Ong PW, Rosli R, Masura SS, Murphy DJ,
Sambanthamurthi R, Haslam RP, Chye ML, Harwood JL, Low EL (2019) Characterisation of Oil Palm Acyl-CoA-Binding Proteins and Correlation of their Gene Expression with Oil Synthesis. Plant Cell Physiol. doi: 10.1093/pcp/pcz237.
Nadzirah
Amiruddin is lead author on this Malaysian-led research that includes
collaborators from the University of South Wales, Rothamsted Research
and Cardiff University. This paper looks at the expression of
Acyl-CoA-binding proteins (ACBPs) in oil palm; providing important
information about the role of this protein family during oil synthesis
in the world’s most important oil crop.
Wang L, Sun J, Lin L, Fu Y, Alenius H, Lindsey K, Chen C (2019) Silver nanoparticles regulate Arabidopsis root growth by concentration-dependent modification of reactive oxygen species accumulation and cell division. Ecotoxicol Environ Saf. doi: 10.1016/j.ecoenv.2019.110072.
This Chinese-study is led by Likai Wang and includes Keith Lindsey from Durham University as a co-author. They look at the effect of silver nanoparticles (AgNPs) on growth of Arabidopsis. AgNPs are taken up by roots and have opposing effects at either 50 mg L-1 or 100mg mg L-1. This is an important preliminary study to understand how plant growth might be altered if AgNP’s are used as a delivery mechanism.
Naramoto S, Jones VAS, Trozzi N, Sato M, Toyooka K, Shimamura M, Ishida S, Nishitani K, Ishizaki K, Nishihama R, Kohchi T, Dolan L, Kyozuka J (2019) A conserved regulatory mechanism mediates the convergent evolution of plant shoot lateral organs. PLoS Biol. 2019 doi: 10.1371/journal.pbio.3000560 Open Access
This Japanese study is led by Satoshi Naramoto and Junko Kyozuka and includes co-authors from the University of Oxford. They performed a mutant screen in the liverwort Marchantia polymorpha to identify the LATERAL ORGAN SUPRESSOR 1 (MpLOS1) gene, which regulates meristem maintenance and lateral organ development. Remarkably they showed this gene is also functions in the control of lateral organ development in rice, therefore demonstrating convergent evolution across plant lineages in the control of lateral organs.
Del Pozo A, Méndez-Espinoza AM, Romero-Bravo S, Garriga M, Estrada F, Alcaíno M, Camargo-Rodriguez AV, Corke FMK, Doonan JH, Lobos GA (2020) Genotypic variations in leaf and whole-plant water use efficiencies are closely related in bread wheat genotypes under well-watered and water-limited conditions during grain filling. Sci Rep. doi: 10.1038/s41598-019-57116-0 Open Access
Alejandro del Pozo leads this Chilean study that includes co-authors from Aberystwyth and NIAB. This large-scale glasshouse experiment looked at the effect of water deficit on the growth of 14 bread wheat genotypes. Measurement of multiple parameters revealed that plants face limitations to the assimilation process during grain filling due to natural senesce and water stress.