OsCIPK31, a CBL-interacting protein kinase is involved in germination and seedling growth under abiotic stress conditions in rice plants.
Calcineurin B-like protein-interacting protein kinases (CIPKs) are a group of typical Ser/Thr protein kinases that mediate calcium signals. Extensive studies using Arabidopsis plants have demonstrated that many calcium signatures that activate CIPKs originate from abiotic stresses. However, there are few reports on the functional demonstration of CIPKs in other plants, especially in grasses. In this study, we used a loss-of-function mutation to characterize the function of the rice CIPK gene OsCIPK31. Exposure to high concentrations of NaCl or mannitol effected a rapid and transient enhancement of OsCIPK31 expression. These findings were observed only in the light. However, longer exposure to most stresses resulted in downregulation of OsCIPK31 expression in both the presence and absence of light. To determine the physiological roles of OsCIPK31 in rice plants, the sensitivity of oscipk31::Ds, which is a transposon Ds insertion mutant, to abiotic stresses was examined during germination and seedling stages. oscipk31::Ds mutants exhibited hypersensitive phenotypes to ABA, salt, mannitol, and glucose. Compared with wild-type rice plants, mutants exhibited retarded germination and slow seedling growth. In addition, oscipk31::Ds seedlings exhibited enhanced expression of several stress-responsive genes after exposure to these abiotic stresses. However, the expression of ABA metabolic genes and the endogenous levels of ABA were not altered significantly in the oscipk31::Ds mutant. This study demonstrated that rice plants use OsCIPK31 to modulate responses to abiotic stresses during the seed germination and seedling stages and to modulate the expression of stress-responsive genes.
Piao
Hai-long
HL
Division of Applied Life Science (Brain Korea 21 Program), Plant Molecular Biology and Biotechnology Research Center, Environmental Biotechnology National Core Research Center, Gyeongsang National University, Jinju 660-701, Korea.
Xuan
Yuan-hu
YH
Park
Su Hyun
SH
Je
Byoung Il
BI
Park
Soon Ju
SJ
Park
Sung Han
SH
Kim
Chul Min
CM
Huang
Jin
J
Wang
Guo Kui
GK
Kim
Min Jung
MJ
Kang
Sang Mo
SM
Lee
In-Jung
IJ
Kwon
Taek-Ryoun
TR
Kim
Yong Hwan
YH
Yeo
Un-sang
US
Yi
Gihwan
G
Son
DaeYoung
D
Han
Chang-deok
CD
D000595:Amino Acid Sequence; D017360:Arabidopsis / Q000201:enzymology / Q000235:genetics / Q000254:growth & development; D018507:Gene Expression Regulation, Developmental; D018506:Gene Expression Regulation, Plant; D018525:Germination; D006801:Humans; D008969:Molecular Sequence Data; D012275:Oryza / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D010937:Plant Growth Regulators / Q000494:pharmacology; D030821:Plants, Genetically Modified; D017346:Protein Serine-Threonine Kinases / Q000096:biosynthesis / Q000235:genetics / Q000502:physiology*; D036226:Seedlings / Q000201:enzymology / Q000235:genetics* / Q000254:growth & development; D013312:Stress, Physiological / Q000235:genetics*
D010937:Plant Growth Regulators; D017346:Protein Serine-Threonine Kinases