A high content in lipid-modified peripheral proteins and integral receptor kinases features in the arabidopsis plasma membrane proteome.
The proteomics of plasma membrane has brought to date only scarce and partial information on the actual protein repertoire. In this work, the plant plasma membrane proteome of Arabidopsis thaliana was investigated. A highly purified plasma membrane fraction was washed by NaCl and Na2CO3 salts, and the insoluble fractions were further analyzed by nano-LC-MS/MS. With 446 proteins identified, we hereby describe the largest plasma membrane proteome diversity reported so far. Half of the proteins were predicted to display transmembrane domains and/or to be anchored to the membrane, validating a posteriori the pertinence of the approach. A fine analysis highlighted two main specific and novel features. First, the main functional category is represented by a majority of as yet unreported signaling proteins, including 11% receptor-like kinases. Second, 16% of the identified proteins are predicted to be lipid-modified, specifically involving double lipid linkage through N-terminal myristoylation, S-palmitoylation, C-terminal prenylation, or glycosylphosphatidylinositol anchors. Thus, our approach led for the first time to the identification of a large number of peripheral proteins as part of the plasma membrane and allowed the functionality of the plasma membrane in the cell context to be reconsidered.
Marmagne
Anne
A
Institut des Sciences du Végétal, CNRS-UPR 2355, Bât 22, avenue de la Terrasse, 91198 Gif sur Yvette Cedex, France.
Ferro
Myriam
M
Meinnel
Thierry
T
Bruley
Christophe
C
Kuhn
Lauriane
L
Garin
Jérome
J
Barbier-Brygoo
Hélène
H
Ephritikhine
Geneviève
G
D017360:Arabidopsis / Q000737:chemistry*; D029681:Arabidopsis Proteins / Q000032:analysis*; D002462:Cell Membrane / Q000737:chemistry; D002853:Chromatography, Liquid; D008055:Lipids / Q000032:analysis; D054878:Lipoylation; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000032:analysis*; D010770:Phosphotransferases / Q000032:analysis; D020543:Proteome / Q000032:analysis*; D040901:Proteomics; D012492:Salts / Q000737:chemistry
D029681:Arabidopsis Proteins; D008055:Lipids; D008565:Membrane Proteins; D020543:Proteome; D012492:Salts; D010770:Phosphotransferases