CIPK3, a calcium sensor-associated protein kinase that regulates abscisic acid and cold signal transduction in Arabidopsis.
Plants respond to environmental stress by activating "stress genes." The plant hormone abscisic acid (ABA) plays an important role in stress-responsive gene expression. Although Ca(2+) serves as a common second messenger in signaling stress and ABA, little is known about the molecular basis of Ca(2+) action in these pathways. Here, we show that CIPK3, a Ser/Thr protein kinase that associates with a calcineurin B-like calcium sensor, regulates ABA response during seed germination and ABA- and stress-induced gene expression in Arabidopsis. The expression of the CIPK3 gene itself is responsive to ABA and stress conditions, including cold, high salt, wounding, and drought. Disruption of CIPK3 altered the expression pattern of a number of stress gene markers in response to ABA, cold, and high salt. However, drought-induced gene expression was not altered in the cipk3 mutant plants, suggesting that CIPK3 regulates select pathways in response to abiotic stress and ABA. These results identify CIPK3 as a molecular link between stress- and ABA-induced calcium signal and gene expression in plant cells. Because the cold signaling pathway is largely independent of endogenous ABA production, CIPK3 represents a cross-talk "node" between the ABA-dependent and ABA-independent pathways in stress responses.
Kim
Kyung-Nam
KN
Department of Plant and Microbial Biology, University of California, Berkeley, California 94720, USA.
Cheong
Yong Hwa
YH
Grant
John J
JJ
Pandey
Girdhar K
GK
Luan
Sheng
S
D000040:Abscisic Acid / Q000494:pharmacology*; D017360:Arabidopsis / Q000187:drug effects / Q000201:enzymology* / Q000235:genetics; D029681:Arabidopsis Proteins / Q000235:genetics* / Q000378:metabolism; D002118:Calcium / Q000378:metabolism; D002135:Calcium-Binding Proteins / Q000235:genetics / Q000378:metabolism; D003080:Cold Temperature; D015971:Gene Expression Regulation, Enzymologic / Q000187:drug effects; D018506:Gene Expression Regulation, Plant / Q000187:drug effects; D018525:Germination / Q000187:drug effects / Q000235:genetics; D009154:Mutation; D017346:Protein Serine-Threonine Kinases / Q000235:genetics* / Q000378:metabolism; D012639:Seeds / Q000235:genetics / Q000254:growth & development / Q000378:metabolism; D015398:Signal Transduction; D012965:Sodium Chloride / Q000494:pharmacology; D013314:Stress, Mechanical; D014867:Water / Q000494:pharmacology
D000040:Abscisic Acid; D029681:Arabidopsis Proteins; D002118:Calcium; D002135:Calcium-Binding Proteins; D017346:Protein Serine-Threonine Kinases; D012965:Sodium Chloride; D014867:Water; C484078:CBL10 protein, Arabidopsis; C484079:CBL3 protein, Arabidopsis; C483419:calcineurin B-like protein 1, Arabidopsis; C474211:CIPK3 protein, Arabidopsis; C480758:At5g55990 protein, Arabidopsis