title: New changes in the plasma-membrane-associated proteome of rice roots under salt stress.
abstract: To gain a better understanding of salt stress responses in plants, we used a proteomic approach to investigate changes in rice (Oryza sativa) root plasma-membrane-associated proteins following treatment with 150 mmol/L NaCl. With or without a 48 h salt treatment, plasma membrane fractions from root tip cells of a salt-sensitive rice cultivar, Wuyunjing 8, were purified by PEG aqueous two-phase partitioning, and plasma-membrane-associated proteins were separated by IEF/SDS-PAGE using an optimized rehydration buffer. Comparative analysis of three independent biological replicates revealed that the expressions of 18 proteins changed by more than 1.5-fold in response to salt stress. Of these proteins, nine were up-regulated and nine were down-regulated. MS analysis indicated that most of these membrane-associated proteins are involved in important physiological processes such as membrane stabilization, ion homeostasis, and signal transduction. In addition, a new leucine-rich-repeat type receptor-like protein kinase, OsRPK1, was identified as a salt-responding protein. Immuno-blots indicated that OsRPK1 is also induced by cold, drought, and abscisic acid. Using immuno-histochemical techniques, we determined that the expression of OsRPK1 was localized in the plasma membrane of cortex cells in roots. The results suggest that different rice cultivars might have different salt stress response mechanisms.
authors.affiliation: Department of Biochemistry and Molecular Biology, College of Life Science, Nanjing Agricultural University, Nanjing, Jiangsu, PR China.
authors.forename: Yanwei
authors.initials: Y
authors.lastname: Cheng
authors.forename: Yaocheng
authors.initials: Y
authors.lastname: Qi
authors.forename: Qian
authors.initials: Q
authors.lastname: Zhu
authors.forename: Xi
authors.initials: X
authors.lastname: Chen
authors.forename: Ning
authors.initials: N
authors.lastname: Wang
authors.forename: Xin
authors.initials: X
authors.lastname: Zhao
authors.forename: Haiyan
authors.initials: H
authors.lastname: Chen
authors.forename: Xiangju
authors.initials: X
authors.lastname: Cui
authors.forename: Langlai
authors.initials: L
authors.lastname: Xu
authors.forename: Wei
authors.initials: W
authors.lastname: Zhang
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism; D000251:Adenosine Triphosphatases / Q000378:metabolism; D002462:Cell Membrane / Q000378:metabolism / Q000648:ultrastructure; D055864:Droughts; D015180:Electrophoresis, Gel, Two-Dimensional; D008315:Malondialdehyde / Q000378:metabolism; D013058:Mass Spectrometry; D008565:Membrane Proteins / Q000378:metabolism*; D012275:Oryza / Q000378:metabolism*; D009195:Peroxidase / Q000378:metabolism; D010940:Plant Proteins / Q000378:metabolism; D018517:Plant Roots / Q000378:metabolism*; D011494:Protein Kinases / Q000378:metabolism; D020543:Proteome / Q000378:metabolism*; D015398:Signal Transduction / Q000187:drug effects; D012965:Sodium Chloride / Q000494:pharmacology*; D013312:Stress, Physiological / Q000502:physiology*
chemical_list: D008565:Membrane Proteins; D010940:Plant Proteins; D020543:Proteome; D012965:Sodium Chloride; D008315:Malondialdehyde; D000040:Abscisic Acid; D009195:Peroxidase; D011494:Protein Kinases; D000251:Adenosine Triphosphatases