Abiotic stress-inducible receptor-like kinases negatively control ABA signaling in Arabidopsis.
Membrane-anchored receptor-like protein kinases (RLKs) recognize extracellular signals at the cell surface and activate the downstream signaling pathway by phosphorylating specific target proteins. We analyzed a receptor-like cytosolic kinase (RLCK) gene, ARCK1, whose expression was induced by abiotic stress. ARCK1 belongs to the cysteine-rich repeat (CRR) RLK sub-family and encodes a cytosolic protein kinase. The arck1 mutant showed higher sensitivity than the wild-type to ABA and osmotic stress during the post-germinative growth phase. CRK36, an abiotic stress-inducible RLK belonging to the CRR RLK sub-family, was screened as a potential interacting factor with ARCK1 by co-expression analyses and a yeast two-hybrid system. CRK36 physically interacted with ARCK1 in plant cells, and the kinase domain of CRK36 phosphorylated ARCK1 in vitro. We generated CRK36 RNAi transgenic plants, and found that transgenic plants with suppressed CRK36 expression showed higher sensitivity than arck1-2 to ABA and osmotic stress during the post-germinative growth phase. Microarray analysis using CRK36 RNAi plants revealed that suppression of CRK36 up-regulates several ABA-responsive genes, such as LEA genes, oleosin, ABI4 and ABI5. These results suggest that CRK36 and ARCK1 form a complex and negatively control ABA and osmotic stress signal transduction.
Laboratory of Plant Molecular Physiology, Graduate School of Agricultural and Life Sciences, The University of Tokyo, Bunkyo-ku, Tokyo, Japan.
Hidenori
H
Tanaka
Yuriko
Y
Osakabe
Shogo
S
Katsura
Shinji
S
Mizuno
Kyonoshin
K
Maruyama
Kazuya
K
Kusakabe
Junya
J
Mizoi
Kazuo
K
Shinozaki
Kazuko
K
Yamaguchi-Shinozaki
D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000235:genetics* / Q000254:growth & development / Q000378:metabolism; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D015153:Blotting, Western; D003080:Cold Temperature; D020869:Gene Expression Profiling; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000235:genetics; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D018613:Microscopy, Confocal; D009154:Mutation; D020411:Oligonucleotide Array Sequence Analysis; D010766:Phosphorylation; D010937:Plant Growth Regulators / Q000494:pharmacology; D030821:Plants, Genetically Modified; D011485:Protein Binding; D011494:Protein Kinases / Q000235:genetics* / Q000378:metabolism; D034622:RNA Interference; D020133:Reverse Transcriptase Polymerase Chain Reaction; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015398:Signal Transduction / Q000235:genetics; D012965:Sodium Chloride / Q000494:pharmacology; D020798:Two-Hybrid System Techniques; D014867:Water / Q000494:pharmacology
D029681:Arabidopsis Proteins; D010937:Plant Growth Regulators; D014867:Water; D049452:Green Fluorescent Proteins; D012965:Sodium Chloride; D000040:Abscisic Acid; C574785:ARCK1 protein, Arabidopsis; D011494:Protein Kinases; C574786:cysteine-rich receptor-like protein kinase 36, Arabidopsis