W55a encodes a novel protein kinase that is involved in multiple stress responses.
Protein kinases play crucial roles in response to external environment stress signals. A putative protein kinase, W55a, belonging to SNF1-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.
Xu
Zhao-Shi
ZS
National Key Facility of Crop Gene Resources and Genetic Improvement, Key Laboratory of Crop Genetics and Breeding, Ministry of Agriculture, Institute of Crop Science, the Chinese Academy of Agricultural Sciences, Beijing 100081, China.
Liu
Li
L
Ni
Zhi-Yong
ZY
Liu
Pei
P
Chen
Ming
M
Li
Lian-Cheng
LC
Chen
Yao-Feng
YF
Ma
You-Zhi
YZ
D000222:Adaptation, Physiological; D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000235:genetics; D001483:Base Sequence; D032461:Chromosomes, Plant / Q000235:genetics; D018076:DNA, Complementary / Q000235:genetics / Q000302:isolation & purification; D055864:Droughts; D020869:Gene Expression Profiling; D018506:Gene Expression Regulation, Plant; D017343:Genes, Plant; D008969:Molecular Sequence Data; D010802:Phylogeny; D018515:Plant Leaves / Q000235:genetics; D010940:Plant Proteins / Q000737:chemistry / Q000235:genetics*; D030821:Plants, Genetically Modified; D011494:Protein Kinases / Q000737:chemistry / Q000235:genetics*; D012333:RNA, Messenger / Q000235:genetics / Q000378:metabolism; D016415:Sequence Alignment; D017422:Sequence Analysis, DNA; D013312:Stress, Physiological; D014908:Triticum / Q000201:enzymology* / Q000235:genetics
D018076:DNA, Complementary; D010940:Plant Proteins; D012333:RNA, Messenger; D011494:Protein Kinases