RRC ID 33099
著者 Tsugama D, Liu S, Takano T.
タイトル Analysis of functions of VIP1 and its close homologs in osmosensory responses of Arabidopsis thaliana.
ジャーナル PLoS One
Abstract VIP1 is a bZIP protein in Arabidopsis thaliana. VIP1 accumulates in the nucleus under hypo-osmotic conditions and interacts with the promoters of hypo-osmolarity-responsive genes, CYP707A1 and CYP707A3 (CYP707A1/3), but neither overexpression of VIP1 nor truncation of its DNA-binding region affects the expression of CYP707A3 in vivo, raising the possibility that VIP and other proteins are functionally redundant. Here we show further analyses on VIP1 and its close homologs, namely, Arabidopsis group I bZIP proteins. The patterns of the signals of the GFP-fused group I bZIP proteins were similar in onion and Arabidopsis cells, suggesting that they have similar subcellular localization. In a yeast one-hybrid assay, the group I bZIP proteins caused reporter gene activation in the yeast reporter strain. VIP1 and other group I bZIP proteins showed positive results in a yeast two-hybrid assay and a bimolecular fluorescence complementation assay, suggesting that they physically interact. These results support the idea that they have somewhat similar functions. By gel shift assays, VIP1-binding sequences in the CYP707A1/3 promoters were confirmed to be AGCTGT/G. Their presence in the promoters of the genes that respond to hypo-osmotic conditions was evaluated using previously published microarray data. Interestingly, a significantly higher proportion of the promoters of the genes that were up-regulated by rehydration treatment and/or submergence treatment (treatment by a hypotonic solution) and a significantly lower proportion of the promoters of the genes that were down-regulated by such treatment shared AGCTGT/G. To further assess the physiological role of VIP1, constitutively nuclear-localized variants of VIP1 were generated. When overexpressed in Arabidopsis, some of them as well as VIP1 caused growth retardation under a mannitol-stressed condition, where VIP1 is localized mainly in the cytoplasm. This raises the possibility that the expression of VIP1 itself rather than its nuclear localization is responsible for regulating the mannitol responses.
巻・号 9(8)
ページ e103930
公開日 2014-1-1
DOI 10.1371/journal.pone.0103930
PII PONE-D-14-23596
PMID 25093810
PMC PMC4122391
MeSH Arabidopsis / genetics* Arabidopsis / metabolism* Arabidopsis Proteins / genetics Arabidopsis Proteins / metabolism Arabidopsis Proteins / physiology* Dehydration / genetics Dehydration / metabolism Gene Expression Profiling Gene Expression Regulation, Plant / drug effects Genes, Plant Mannitol / pharmacology Microarray Analysis Osmoregulation / drug effects Osmoregulation / genetics* Plants, Genetically Modified Promoter Regions, Genetic / drug effects Sequence Homology
IF 2.74
引用数 23
WOS 分野 PLANT SCIENCES
リソース情報
シロイヌナズナ / 植物培養細胞・遺伝子 pda03704 pda03854 pda04166 pda04204 pda06392 pda07827 pda08749 pda20227