ARABIDOPSIS RESEARCH ROUND-UPARABIDOPSIS RESEARCH ROUND-UP

20th Nov 2014

Here’s your weekly round-up of the latest Arabidopsis research from the UK, this week including a mixed bag of studies from the Universities of Edinburgh, Oxford, Worcester, Warwick and Nottingham.

 

  • Shi YZ, Zhu XF, Miller JG, Gregson T, Zheng SJ and Fry SC. Distinct catalytic capacities of two aluminium-repressed Arabidopsis thaliana xyloglucan endotransglucosylase/hydrolases, XTH15 and XTH31, heterologously produced in Pichia. Phytochemistry, 27 October 2014. DOI: 10.1016/j.phytochem.2014.09.020.

Janice Miller and Stephen Fry from the University of Edinburgh (with former lab member Tim Gregson now at the Lancaster Environment Centre) worked with Chinese collaborators on this study to further understand the roles of the xyloglucan endotransglucosylase/hydrolases (XTHs). They looked at two very different XTHs – XTH15 and XTH31 – to analyse their modes of action compared to the rest of this enzyme family.

 

  • Berns MC, Nordström K, Cremer F, Tóth R, Hartke M, Simon S, Klasen JR, Bürstel I and Coupland G. Evening expression of Arabidopsis GIGANTEA is controlled by combinatorial interactions among evolutionarily conserved regulatory motifs. The Plant Cell, 27 October 2014. DOI: 10.1105/tpc.114.129437.

Though a former member of the Coupland lab at the Max Planck Institute for Plant Breeding Research, which led this study, Réka Tóth is now on staff at the University of Oxford. This paper explores the role of Arabidopsis GIGANTEA in its contributions to photoperiodic flowering, circadian clock control and photoreceptor signaling; in particular its transcription, which is regulated by light and the circadian clock. Three evolutionarily contrained motifs (CRMs) are identified within the GIGANTEA promoter which, combined with EVENING ELEMENTs and ABA RESPONSE ELEMENT LIKE motifs, contribute to diurnal transcription patterns.

 

  • Andersson MX, Nilsson AK, Johansson ON, et al. Involvement of the electrophilic isothiocyanate sulforaphane in Arabidopsis local defense responses. Plant Physiology, 3 November 2014. DOI: 10.1104/pp.114.251892.

Working with Swedish and American partners, Gülin Boztas and Mahmut Tör from the University of Worcester were also collaborators on this paper. While the hypersenstive response of plants to pathogen effector molecules has long been documented, this research provides new detail on the nature of that response; specifically that sulforaphane – a compound triggering programmed cell death - is released by Arabidopsis thaliana when infected by Hyaloperonospora arabidopsidis.

 

  • Piquerez SJ, Harvey SE, Beynon JL and Ntoukakis V. Improving crop disease resistance: lessons from research on Arabidopsis and tomato. Frontiers in Plant Science, 10 November 2014. DOI: 10.3389/fpls.2014.00671. [Open Access]

GARNet PI Jim Beynon is co-corresponding author for this helpful review. In it, Jim and colleagues from the University of Warwick describes how the use of Arabidopsis and tomato as model organisms for plant research have contributed knowledge and understanding of plant defense mechanisms, and how these have been and will continue to be applied to modern crop improvement programmes.

 

  • Mellor N, Péret B, Porco S, Sairanen I, Ljung K, Bennett M and King J. Modelling of Arabidopsis LAX3 expression suggests auxin homeostasis. Journal of Theoretical Biology, 13 November 2014. DOI: 10.1016/j.jtbi.2014.11.003.

Former GARNet committee member Malcolm Bennett, together with colleagues from Nottingham, France and Sweden, present this paper in Journal of Theoretical Biology. They describe their development of a single-cell model of the auxin influx carrier LAX3 (which is mediated by the ARF7/19 IAA14 signalling module) to demonstrate that hysteresis and bistability may explain the experimentally observed ‘all-or-nothing’ LAX3 spatial expression pattern in cortical Arabidopsis root cells containing a gradient of auxin concentrations.