Exploring the mechanism of Physcomitrella patens desiccation tolerance through a proteomic strategy.
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.
Wang
Xiao Qin
XQ
College of Life Sciences, Capital Normal University, Beijing 100048, China.
Yang
Ping Fang
PF
Liu
Zheng
Z
Liu
Wei Zhong
WZ
Hu
Yong
Y
Chen
Hui
H
Kuang
Ting Yun
TY
Pei
Zhen Ming
ZM
Shen
Shi Hua
SH
He
Yi Kun
YK
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
D003598:Cytoskeletal Proteins; D010940:Plant Proteins; D020543:Proteome; D002734:Chlorophyll