title: OsWRKY45 alleles play different roles in abscisic acid signalling and salt stress tolerance but similar roles in drought and cold tolerance in rice.
abstract: Although allelic diversity of genes has been shown to contribute to many phenotypic variations associated with different physiological processes in plants, information on allelic diversity of abiotic stress-responsive genes is limited. Here it is shown that the alleles OsWRKY45-1 and OsWRKY45-2 play different roles in abscisic acid (ABA) signalling and salt stress adaptation in rice. The two alleles had different transcriptional responses to ABA and salt stresses. OsWRKY45-1-overexpressing lines showed reduced ABA sensitivity, whereas OsWRKY45-1-knockout lines showed increased ABA sensitivity. OsWRKY45-1 transgenic plants showed no obvious difference from negative controls in response to salt stress. In contrast, OsWRKY45-2-overexpressing lines showed increased ABA sensitivity and reduced salt stress tolerance, and OsWRKY45-2-suppressing lines showed reduced ABA sensitivity and increased salt stress tolerance. OsWRKY45-1 and OsWRKY45-2 transgenic plants showed differential expression of a set of ABA- and abiotic stress-responsive genes, but they showed similar responses to cold and drought stresses. These results suggest that OsWRKY45-1 negatively and OsWRKY45-2 positively regulates ABA signalling and, in addition, OsWRKY45-2 but not OsWRKY45-1 negatively regulates rice response to salt stress. The different roles of the two alleles in ABA signalling and salt stress may be due to their transcriptional mediation of different signalling pathways.
authors: National Key Laboratory of Crop Genetic Improvement, National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
authors: Zeng
authors: Z
authors: Tao
authors: Yanjun
authors: Y
authors: Kou
authors: Hongbo
authors: H
authors: Liu
authors: Xianghua
authors: X
authors: Li
authors: Jinghua
authors: J
authors: Xiao
authors: Shiping
authors: S
authors: Wang
mesh_terms: D000040:Abscisic Acid / Q000378:metabolism*; D000483:Alleles; D003080:Cold Temperature; D055864:Droughts; D018506:Gene Expression Regulation, Plant; D012275:Oryza / Q000235:genetics / Q000502:physiology*; D010940:Plant Proteins / Q000235:genetics* / Q000378:metabolism*; D015398:Signal Transduction; D012965:Sodium Chloride / Q000378:metabolism*; D013312:Stress, Physiological; D014157:Transcription Factors / Q000235:genetics* / Q000378:metabolism*
chemical_list: D010940:Plant Proteins; D014157:Transcription Factors; D012965:Sodium Chloride; D000040:Abscisic Acid