Caracterisation de la prise d'oxygene a la lumiere chez deux vegetaux modeles : influence d'un regulateur de croissance sur les echanges gazeux

SIGLECNRS T Bordereau / INIST-CNRS - Institut de l'Information Scientifique et TechniqueFRFranc

Identification of a lysyl residue defining the binding specificity of a human odorant-binding protein

International audienc

Identification of a lysyl residue defining the binding specificity of a human odorant-binding protein

International audienc

Odorant binding and conformational changes of a rat odorant-binding protein

International audienc

Simultaneous identification and quantification of nitrosylation sites by combination of biotin switch and ICAT labeling

S-nitrosylation is a widespread modification of proteins. In plants, most information available to date regarding this modification was obtained using nitric oxide donors and concerned the proteins but not the identification of cysteine residues specifically modified in the proteins or their quantification. Here, we describe a method for the identification of endogenously nitrosylated cysteines in Arabidopsis and, simultaneously, the measurement of relative change in their abundance within binary comparisons

Is the hamster lipocalin aphrodisin a pheromone or a pheromone carrier ?

National audienc

Phosphoproteomic analysis reveals major default phosphorylation sites outside long intrinsically disordered regions of [i]Arabidopsis[/i] plasma membrane proteins.

Background: Genome-wide statistics established that long intrinsically disordered regions (over 30 residues) are predicted in a large part of proteins in all eukaryotes, with a higher ratio in trans-membrane proteins. At functional level, such unstructured and flexible regions were suggested for years to favour phosphorylation events. In plants, despite increasing evidence of the regulation of transport and signalling processes by phosphorylation events, only few data are available without specific information regarding plasma membrane proteins, especially at proteome scale. Results: Using a dedicated phosphoproteomic workflow, 75 novel and unambiguous phosphorylation sites were identified in Arabidopsis plasma membrane. Bioinformatics analysis showed that this new dataset concerned mostly integral proteins involved in key functions of the plasma membrane (such as transport and signal transduction, including protein phosphorylation). It thus expanded by 15% the directory of phosphosites previously characterized in signalling and transport proteins. Unexpectedly, 66% of phosphorylation sites were predicted to be located outside long intrinsically disordered regions. This result was further corroborated by analysis of publicly available data for the plasma membrane. Conclusions: The new phosphoproteomics data presented here, with published datasets and functional annotation, suggest a previously unexpected topology of phosphorylation in the plant plasma membrane proteins. The significance of these new insights into the so far overlooked properties of the plant plasma membrane phosphoproteome and the long disordered regions is discussed