ARABIDOPSIS RESEARCH ROUND-UPARABIDOPSIS RESEARCH ROUND-UP

19th Aug 2013

Publishers have been busy publishing lots of new Arabidopsis research articles this week! Here’s your Arabidopsis research round-up, just in case you missed them.

 

• Geshi N, Johansen JN, Dilokpimol A, et al. A galactosyltransferase acting on arabinogalactan protein glycans is essential for embryo development in Arabidopsis. The Plant Journal, 10 August 2013. DOI: 10.1111/tpj.12281.

This paper describes the findings that an Arabidopsis glycosyltransferase, AtGALT31A, is involved in the elongation of arabinogalactan protein side chains by galactosylation. Furthermore, the research team, which included Dr Theodora Tryfona from the University of Cambridge’s Department of Biochemistry, show that a mutation in the AtGALT31A gene causes arrest of embryo development at the globular stage.

 

• Ryu JY, Lee H-Y, Seo PJ, Jung J-H, Ahn JH and Park C-M. The Arabidopsis floral repressor BFT delays flowering by competing with FT for FD binding under high salinity. Molecular Plant, 10 August 2013. DOI: 10.1093/mp/sst114.

In previous work, The Sainsbury Laboratory’s Jae-Hoon Jung and colleagues from Korea demonstrated that Arabidopsis BROTHER OF FT AND TFL1 (BFT) acts as a floral repressor under salt stress, but the molecular mechanisms underlying this BFT function was unknown. Building on this work, this new paper describes how BFT delays flowering in Arabidopsis by competing with FLOWERING LOCUS T (FT) for binding to the FD transcription factor.

 

• Higham CF and Husmeier D. A Bayesian approach for parameter estimation in the extended clock gene circuit of Arabidopsis thaliana. BMC Bioinformatics, 12 August 2013. DOI: 10.1186/1471-2105-14-S10-S3.

This paper by Catherine Higham and Dirk Husmeier from the University of Glasgow was published in a BMC Bioinformatics supplement of selected articles from the 10th International Workshop on Computational Systems Biology. Here, Higham and Husmeier describe advances on the work of Pokhilko et al., who developed a deterministic ODE mathematical model of the plant circadian clock in order to understand the behaviour, mechanisms and properties of the system.

 

• Galbiati F, Roy DS, Simonini S, et al. An integrative model of the control of ovule primordial formation. The Plant Journal, 13 August 2013. DOI: 10.1111/tpj.12309.

The international research team behind this paper includes scientists from Austria, Belgium, Italy, Germany, Japan, the Netherlands, and Sara Simonini who is currently based at the John Innes Centre in Norwich. Here they describe how the genes CUC1 and CUC2 are involved in the regulation of PIN1 expression, which is in turn is needed for ovule primordia formation and ultimately determines crop seed yield. Based on these findings, an integrative model for the molecular mechanisms of the early stages of ovule development is proposed.

 

• Vanholme R, Cesarino I, Rataj K, et al. Caffeoyl shikimate esterase (CSE) is an enzyme in the lignin biosynthetic pathway. Science, 15 August 2013. DOI: 10.1126/science.1241602.

Claire Halpin, Lydia Welsh and Gordon Simpson – all working at the James Hutton Institute in Dundee – contributed to this paper in which it was found that Arabidopsis thaliana plants with a mutation in the gene for caffeoyl shikimate esterase (CSE) deposit less lignin in the cell walls. Since high lignin content limits the amount of cellulose that can be hydrolysed to glucose in biorefining, production of biomass feedstocks with less lignin could allow development of more efficient biofuels. See also here

 

• Werner AK, Medina-Escobar N, Zulawski M, Sparkes IA, Cao F-Q, and Witte C-P. The ureide degrading reactions of purine ring catabolism employ four amino- and amidohydrolases in Arabidopsis and soybean. Plant Physiology, August 2013. DOI: 10.1104/pp.113.224261.

In some legumes, such as soybean, ureides, including allantoin, are used for nodule to shoot translocation of fixed nitrogen. Although four Arabidopsis genes involved in this pathway have been identified in vitro, the metabolic route in vivo is not well understood. In this paper, which involved researchers from Germany and China, as well as Imogen Sparkes from the University of Exeter, it is demonstrated that allantoinase (ALN), allantoate amidohydrolase (AAH), ureidoglyceine aminohydrolase (UGlyAH) and ureidoglycolate amidohydrolase (UAH) are required for allantoin degradation in vivo.

 

• Crumpton-Taylor M, Pike M, Lu K-J, Hylton CM, Feil R, Eicke S, Lunn JE, Zeeman SC and Smith AM. Starch synthase 4 is essential for coordination of starch granule formation with chloroplast division during Arabidopsis leaf expansion. New Phytologist, 19 August 2013. DOI: 10.1111/nph.12455.

Researchers from the John Innes Centre in Norwich, along with colleagues in Switzerland and Germany, have identified that the SS4 isoform of starch synthase is an essential component of a mechanism that coordinates starch granule formation with chloroplast division during leaf expansion in Arabidopsis. Furthermore, SS4 also determines the abundance and the shape of leaf starch granules.