W55a Encodes a Novel Protein Kinase That Is Involved in Multiple Stress Responses  

作　　者：Zhao-Shi Xu Li Liu Zhi-Yong Ni Pei Liu Ming Chen Lian-Cheng Li Yao-Feng Chen You-Zhi Ma 

机构地区：[1]National Key Facility of Crop Gene Resources and Genetic Improvement (NFCRI), Key Laboratory of Crop Genetics and Breeding, Ministry of Agriculture, Institute of Crop Science, the Chinese Academy of Agricultural Sciences (CAAS), Beijing 100081, China [2]Agronomy College, Northwest Sci-Tech University of Agriculture and Forestry, Yangling 712100, China

出　　处：《Journal of Integrative Plant Biology》2009年第1期58-66,共9页植物学报（英文版）

基　　金：Supported by the Hi-Tech Research and Development Program (863) of China (2007AA10Z130);the National Natural Science Foundation ofChina (30700504).

摘　　要：Protein kinases play crucial roles in response to external environment stress signals. A putative protein kinase, W55a, belonging to SNFl-related protein kinase 2 （SnRK2） subfamily, was isolated from a cDNA library of drought-treated wheat seedlings. The entire length of W55a was obtained using rapid amplification of 5＇ cDNA ends （5＇-RACE） and reverse transcription-polymerase chain reaction（RT-PCR）. It contains a 1 029-bp open reading frame （ORF） encoding 342 amino acids. The deduced amino acid sequence of W55a had eleven conserved catalytic subdomains and one Ser/Thr protein kinase active-site that characterize Ser/Thr protein kinases. Phylogenetic analysis showed that W55a was 90.38% homologous with rice SAPK1, a member of the SnRK2 family. Using nullisomic-tetrasomic and ditelocentric lines of Chinese Spring, W55a was located on chromosome 2BS. Expression pattern analysis revealed that W55a was upregulated by drought and salt, exogenous abscisic acid, salicylic acid, ethylene and methyl jasmonate, but was not responsive to cold stress. In addition, W55a transcripts were abundant in leaves, but not in roots or stems, under environmental stresses. Transgenic Arabidopsis plants overexpressing W55a exhibited higher tolerance to drought. Based on these findings, W55a encodes a novel dehydration-responsive protein kinase that is involved in multiple stress signal transductions.Protein kinases play crucial roles in response to external environment stress signals. A putative protein kinase, W55a, belonging to SNFl-related protein kinase 2 （SnRK2） subfamily, was isolated from a cDNA library of drought-treated wheat seedlings. The entire length of W55a was obtained using rapid amplification of 5＇ cDNA ends （5＇-RACE） and reverse transcription-polymerase chain reaction（RT-PCR）. It contains a 1 029-bp open reading frame （ORF） encoding 342 amino acids. The deduced amino acid sequence of W55a had eleven conserved catalytic subdomains and one Ser/Thr protein kinase active-site that characterize Ser/Thr protein kinases. Phylogenetic analysis showed that W55a was 90.38% homologous with rice SAPK1, a member of the SnRK2 family. Using nullisomic-tetrasomic and ditelocentric lines of Chinese Spring, W55a was located on chromosome 2BS. Expression pattern analysis revealed that W55a was upregulated by drought and salt, exogenous abscisic acid, salicylic acid, ethylene and methyl jasmonate, but was not responsive to cold stress. In addition, W55a transcripts were abundant in leaves, but not in roots or stems, under environmental stresses. Transgenic Arabidopsis plants overexpressing W55a exhibited higher tolerance to drought. Based on these findings, W55a encodes a novel dehydration-responsive protein kinase that is involved in multiple stress signal transductions.

关 键 词：chromosomal location induction kinetics SnRK2 stress response transgenic Arabidopsis wheat. 

分 类 号：Q945.3[生物学—植物学]