This weeks Arabidopsis Research Roundup bucks the recent trend of featuring large consortium-led studies as it contains four studies each from a single UK Institution. Matthew Jones (Essex) looks at the link between photosynthesis, the circadian clock and blue-light signaling whilst Miriam Gifford (Warwick) uses cell sorting to more precisely define the plants response to an oomycete pathogen. Elsewhere Peter Eastmond (Rothamstead) looks at lipid metabolism and Keith Lindsey (Durham) leads a theorectical study on the effectiveness of methods for modelling hormone crosstalk in the root.
Litthauer S, Battle M, Lawson T, Jones MA (2015) Phototropins Maintain Robust Circadian Oscillation of PSII Operating Efficiency Under Blue Light Plant J. http://dx.doi.org/10.1111/tpj.12947
Matt Jones is a Leuverhulme Research Fellow at the University of Essex and this study is his first output as a group leader. It investigates the affect of the circadian clock on the operating efficiency of photosystem II (PSII). Previous this efficiency had been shown to be controlled by transcriptional feedback loops within the nucleus. However this study shows that in blue light it is maintained by phototropin receptors, which do not influence the nucleus. The novel imaging methodology used in this study highlight differences between the modulation of circadian outputs in distinct subcellular compartments.
Coker TL, Cevik V, Beynon JL, Gifford ML (2015) Spatial dissection of the Arabidopsis thaliana transcriptional response to downy mildew using Fluorescence Activated Cell Sorting Front Plant Sci. http://dx.doi.org/10.3389/fpls.2015.00527
Miriam Gifford leads this study from the University of Warwick that looks at the transcriptional response of Arabidopsis to downy mildew infection. The Gifford lab are experts in analysis of transcriptional data from microarrays. This study uses FACS-sorted cells infected with the biotrophic oomycete pathogen Hyaloperonospora arabidopsidis in an attempt to focus-in on infected cells without the diluting effects of non-infected cells within the same tissue. Almost 300 transcripts were differentially expressed between haustoriated and non-haustoriated cells and this technique uncovered novel genes that had previously not been implicated in playing a role in this pathogen response.
Craddock CP, Adams N, Bryant FM, Kurup S, Eastmond PJ (2015) Regulation of endomembrane biogenesis in Arabidopsis by PHOSPATIDIC ACID HYDROLASE Plant Signal Behav. http://dx.doi.org/10.1080/15592324.2015.1065367
This study was wholly undertaken at Rothamsted Research led by Peter Eastmond. They investigate the coordination of lipid biosynthesis by focussing on the activity of two different enzymes, PHOSPHATIDIC ACID PHOSPHOHYDROLASE (PAH) and PHOSPHOCHOLINE CYTIDYLYLTRANSFERASE (CCT). These enzymes participate in a feedback loop to control the biosynthesis of phosphaticylcholine (PC) and phosphatidic acid (PA), which is linked to biogenesis of the endoplasmic reticulum. This work offers a clue that PAH activity may require phosphorylation even though this data is not yet clear.
Simon Moore, Xiaoxian Zhang, Junli Liu & Keith Lindsey (2015) Some fundamental aspects of modelling auxin patterning in the context of auxin-ethylene-cytokinin crosstalk Plant Signalling and Behaviour http://dx.doi.org/10.1080/15592324.2015.1056424
In this manuscript Keith Lindsey and colleagues from Durham University use the paradigm of root-tip auxin-ethylene-cytokinin signaling to discuss the effectiveness of linking experimental data, reaction kinetics and spatiotemporal modelling to dissect hormonal crosstalk. The authors agree that the integration of kinetic equations with spatial root structure can produce powerful models for assessing the crosstalk of multiple hormone interactions in a spatiotemporal manner. Finally the authors come up with key recommendations to be considered when developing models for spatiotemporal hormonal crosstalk in the Arabidopsis root