Mass spectrometric approach for identifying putative plasma membrane proteins of Arabidopsis leaves associated with cold acclimation

Abstract

SummaryAlthough enhancement of freezing tolerance in plants during cold acclimation is closely associated with an increase in the cryostability of plasma membrane, the molecular mechanism for the increased cryostability of plasma membrane is still to be elucidated. In Arabidopsis, enhanced freezing tolerance was detectable after cold acclimation at 28C for as short as 1 day, and maximum freezing tolerance was attained after 1 week. To identify the plasma membrane proteins that change in quantity in response to cold acclimation, a highly puri®ed plasma membrane fraction was isolated from leaves before and during cold acclimation, and the proteins in the fraction were separated with gel electrophoresis. We found that there were substantial changes in the protein pro®les after as short as 1 day of cold acclimation. Subsequently, using matrix-assisted laser desorption±ionization time-of-¯ight mass spectrometry (MALDI-TOF MS), we identi®ed 38 proteins that changed in quantity during cold acclimation. The proteins that changed in quantity during the ®rst day of cold acclimation include those that are associated with membrane repair by membrane fusion, protection of the membrane against osmotic stress, enhancement of CO 2 ®xation, and proteolysis.

New Evidence for Differential Roles of L10 Ribosomal Proteins from Arabidopsis

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Linking the Salt Transcriptome with Physiological Responses of a Salt-Resistant Populus Species as a Strategy to Identify Genes Important for Stress Acclimation

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