ARABIDOPSIS RESEARCH ROUND-UP
7th Apr 2015
Your UK Arabidopsis Research Round-up this week includes a mixed bag of research, including a basic study that could help improve biofuel production, work on differential metabolism of sphingolipids in pollen, analysis of leaf movements of Arabidopsis plants grown in space, and more!
- Lunn D, Ibbett R, Tucker GA and Lycett GW. Impact of altered cell wall composition on saccharification efficiency in stem tissue of Arabidopsis RABA GTPase-deficient knockout mutants. BioEnergy Research, 13 March 2015. DOI: 10.1007/s12155-015-9599-9. [Open Access]
In an effort to understand how plants can be manipulated for increased biofuel production, this team from the University of Nottingham is exploring a clade of Rab GTPase proteins called RABA. These proteins are involved in the control of trafficking to the cell wall, and their manipulation may help to overcome the cell wall’s inherent recalcitrance to digestion. The group first developed a saccharification process for Arabidopsis, then used this to demonstrate that rab4 mutant lines released more sugar, with or without pre-treatment, on saccharification.
- Luttgeharm KD, Kimberlin AN, Cahoon RE, Cerny RL, Napier JA, Marckham JE and Cahoon EB. Sphingolipid metabolism is strikingly different between pollen and leaf in Arabidopsis as revealed by compositional and gene expression profiling. Phytochemistry, 17 March 2015. DOI: 10.1016/j.phytochem.2015.02.019.
It has been known for some time that sphingolipids are essential for make gametophytic development in Arabidopsis thaliana, but their composition and gene expression patterns have not been studied in pollen. This study, involving the work of Rothamsted’s Johnathan Napier, investigated pollen from wild type Col-0 and a long-chain base Δ4 desaturase mutant. Though we are as yet unsure why, the findings reveal that sphingolipid metabolism is very much different in Arabidopsis pollen compared to leaves.
- Fisahn J, Klingele E and Barlow P. Lunar gravity affects leaf movement of Arabidopsis thaliana in the International Space Station. Planta, 21 March 2015. DOI: 10.1007/s00425-015-2280-x.
Peter Barlow from the University of Bristol is the last author on this study, which takes an interesting look at Arabidopsis plants in space! Using data collected on the International Space Station, Barlow – together with Joachim Fisahn from Germany and Emile Kingele from Switzerland – explored the relationship between oscillations of leaf movements and the lunisolar tide.
- Grison MS, Brocard L, Fouillen L, et al. Specific membrane lipid composition is important for plasmodesmata function in Arabidopsis. The Plant Cell, 27 March 2015. DOI: 10.1105/tpc.114.135731.
Working with French and German collaborators, this paper involves the work of Yoselin Benitez-Alfonso from the University of Leeds. In order to understand more about the roles of the major constituents of the plasma membranes (PMs) of plasmodesmata (PD), the group isolated “native” PD membrane fractions and carried out comparative mass spectrometry analysis. They determined that lipids are laterally segregated along the PM at the PD cell-to-cell junction in Arabidopsis thaliana and that, compared to the bulk of the PM, PD membranes are enriched with sterols and sphingolipids with very long chain saturated fatty acids.
- Massalski C, Bloch J, Zebisch M and Steinebrunner I. The biochemical properties of the Arabidopsis ecto-nucleoside triphosphate diphosphohydrolase AtAPY1 contradict a direct role in purinergic signalling. PLOS ONE, 30 March 2015. DOI: 10.1371/journal.pone.0115832. [Open Access]
Matthias Zebisch from the University of Oxford worked with German colleagues on this PLOS ONE paper, in which the previously assumed role of AtAPY1 is questioned. Previous work proposed that AtAPY1 was involved in growth and development, pollen germination and stress responses through a mechanism involving regulation of extracellular ATP signals. This work shows that ATP is not a substrate of AtAPY1, which is in fact more likely to function as a GDPase.