title: The role of water channel proteins and nitric oxide signaling in rice seed germination.
abstract: Previous studies have demonstrated the possible role of several aquaporins in seed germination. But systematic investigation of the role of aquaporin family members in this process is lacking. Here, the developmental regulation of plasma membrane intrinsic protein (PIP) expression throughout germination and post-germination processes in rice embryos was analyzed. The expression patterns of the PIPs suggest these aquaporins play different roles in seed germination and seedling growth. Partial silencing of the water channel genes, OsPIP1;1 and OsPIP1;3, reduced seed germination while over-expression of OsPIP1;3 promoted seed germination under water-stress conditions. Moreover, spatial expression analysis indicates that OsPIP1;3 is expressed predominantly in embryo during seed germination. Our data also revealed that the nitric oxide (NO) donors, sodium nitroprusside (SNP) and S-nitrosoglutathione (GSNO), promoted seed germination; furthermore, the NO scavenger, 2-(4-carboxyphenyl)-4,4,5,5-tetramethylimidazoline-1-oxyl-3-oxide, inhibited germination and reduced the stimulative effects of SNP and GSNO on rice germination. Exogenous NO stimulated the transcription of OsPIP1;1, OsPIP1;2, OsPIP1;3 and OsPIP2;8 in germinating seeds. These results suggest that water channels play an important role in seed germination, acting, at least partly, in response to the NO signaling pathway.
authors: Institute of Plant Physiology and Ecology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai, China.
authors: Hong-Yan
authors: HY
authors: Liu
authors: Xin
authors: X
authors: Yu
authors: Da-Yong
authors: DY
authors: Cui
authors: Mei-Hao
authors: MH
authors: Sun
authors: Wei-Ning
authors: WN
authors: Sun
authors: Zhang-Cheng
authors: ZC
authors: Tang
authors: Sang-Soo
authors: SS
authors: Kwak
authors: Wei-Ai
authors: WA
authors: Su
mesh_terms: D000040:Abscisic Acid / Q000494:pharmacology; D020346:Aquaporins / Q000235:genetics / Q000378:metabolism / Q000502:physiology*; D001565:Benzoates / Q000494:pharmacology; D015153:Blotting, Western; D003486:Cyanides / Q000494:pharmacology; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D007093:Imidazoles / Q000494:pharmacology; D009569:Nitric Oxide / Q000502:physiology*; D020030:Nitric Oxide Donors / Q000494:pharmacology; D009599:Nitroprusside / Q000494:pharmacology; D012275:Oryza / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D026422:S-Nitrosoglutathione / Q000494:pharmacology; D012639:Seeds / Q000187:drug effects / Q000235:genetics / Q000502:physiology*; D015398:Signal Transduction / Q000187:drug effects; D014867:Water / Q000378:metabolism
chemical_list: D020346:Aquaporins; D001565:Benzoates; D003486:Cyanides; D007093:Imidazoles; D020030:Nitric Oxide Donors; D014867:Water; C079393:1,3-dihydroxy-4,4,5,5-tetramethyl-2-(4-carboxyphenyl)tetrahydroimidazole; D009599:Nitroprusside; D009569:Nitric Oxide; D026422:S-Nitrosoglutathione; D000040:Abscisic Acid