Ting Zhou, Xiyan Yang, Kai Guo, Jinwu Deng, Jiao Xu, Wenhui Gao, Keith Lindsey and Xianlong Zhang.2016.MOL CELL PROTEOMICS
Abstract
Somatic embryogenesis (SE) is a versatile model for understanding the mechanisms of plant embryogenesis and a useful tool for plant propagation. To decipher the intricate molecular program and potentially to control the parameters affecting the frequency of SE, a proteomics approach based on two-dimensional gel electrophoresis (2-DE) combined with MALDI-TOF/TOF was used. A total of 149 unique differentially expressed proteins (DEPs) were identified at different stages of cotton SE compared with the initial control (0 h explants). The expression profile and functional annotation of these DEPs revealed that SE activated stress-related proteins, including several reactive oxygen species (ROS)-scavenging enzymes. Proteins implicated in metabolic, developmental and reproductive processes were also identified. Further experiments were performed to confirm the role ofROS-scavenging enzymes, suggesting the involvement of ROS homeostasis during SE in cotton. Suppressing the expression of specifically identified GhAPX proteins resulted in the inhibition of dedifferentiation. Accelerated redifferentiation was observed in the suppression lines of GhAPXs or GhGSTL3, in parallel with the alteration of endogenous ascorbate metabolism and accumulation of endogenous H2O2 content. Moreover, disrupting endogenous redox homeostasis through the application of high concentration of DPI, H2O2, BSO or GSH inhibited the dedifferentiation of cotton explants. Mild oxidation induced through BSO treatment facilitated the transition from embryogenic calluses (ECs) to somatic embryos. Meanwhile, auxin homeostasis was altered through the perturbation of ROS homeostasis by chemical treatments or suppression of ROS-scavenging proteins, along with the activating/suppressing the transcription of genes related to auxin transportation and signaling. These results show that stress responses are activated during SE, and may regulate the ROS homeostasis by interacting with auxin signaling.
http://www.ncbi.nlm.nih.gov/pubmed/?term=ROS%20homeostasis%20regulates%20somatic%20embryogenesis
pii: mcp.M115.049338. （IF=6.564）
PMID：27073181