title: Exploring the mechanism of Physcomitrella patens desiccation tolerance through a proteomic strategy.
abstract: The moss Physcomitrella patens has been shown to tolerate abiotic stresses, including salinity, cold, and desiccation. To better understand this plant's mechanism of desiccation tolerance, we have applied cellular and proteomic analyses. Gametophores were desiccated over 1 month to 10% of their original fresh weight. We report that during the course of dehydration, several related processes are set in motion: plasmolysis, chloroplast remodeling, and microtubule depolymerization. Despite the severe desiccation, the membrane system maintains integrity. Through two-dimensional gel electrophoresis and image analysis, we identified 71 proteins as desiccation responsive. Following identification and functional categorization, we found that a majority of the desiccation-responsive proteins were involved in metabolism, cytoskeleton, defense, and signaling. Degradation of cytoskeletal proteins might result in cytoskeletal disassembly and consequent changes in the cell structure. Late embryogenesis abundant proteins and reactive oxygen species-scavenging enzymes are both prominently induced, and they might help to diminish the damage brought by desiccation.
authors.affiliation: College of Life Sciences, Capital Normal University, Beijing 100048, China.
authors.forename: Xiao Qin
authors.initials: XQ
authors.lastname: Wang
authors.forename: Ping Fang
authors.initials: PF
authors.lastname: Yang
authors.forename: Zheng
authors.initials: Z
authors.lastname: Liu
authors.forename: Wei Zhong
authors.initials: WZ
authors.lastname: Liu
authors.forename: Yong
authors.initials: Y
authors.lastname: Hu
authors.forename: Hui
authors.initials: H
authors.lastname: Chen
authors.forename: Ting Yun
authors.initials: TY
authors.lastname: Kuang
authors.forename: Zhen Ming
authors.initials: ZM
authors.lastname: Pei
authors.forename: Shi Hua
authors.initials: SH
authors.lastname: Shen
authors.forename: Yi Kun
authors.initials: YK
authors.lastname: He
mesh_terms: D000222:Adaptation, Physiological; D019068:Bryopsida / Q000166:cytology / Q000276:immunology / Q000502:physiology* / Q000648:ultrastructure; D002734:Chlorophyll / Q000378:metabolism; D002853:Chromatography, Liquid; D003598:Cytoskeletal Proteins / Q000378:metabolism; D003890:Desiccation; D015180:Electrophoresis, Gel, Two-Dimensional; D008870:Microtubules / Q000378:metabolism / Q000648:ultrastructure; D010940:Plant Proteins / Q000378:metabolism; D020543:Proteome / Q000378:metabolism; D040901:Proteomics / Q000379:methods*; D015398:Signal Transduction; D013312:Stress, Physiological; D053719:Tandem Mass Spectrometry
chemical_list: D003598:Cytoskeletal Proteins; D010940:Plant Proteins; D020543:Proteome; D002734:Chlorophyll