As a calcium-dependent protein kinase gene in rice, OsCDPK13 (encoded by OsCPK7) is induced by cold and gibberellin in rice leaf sheath.
- OsCDPK13 may catalyze an important phosphorylation event in signaling in rice seedlings under cold stress conditions and in response to GA.
- The OsCDPK13 transcript levels suggested that this kinase might be an important component of signal transduction in rice seedlings under stress conditions and in response to GA.
- OsCDPK13 might affect cell elongation in some way and have an important role in GA-mediated elongation in rice.
GO assignment(s): GO:0004672, GO:0004674, GO:0005509, GO:0005524, GO:0006468
- transgenic rice lines：
- Antisense OsCDPK13 transgenic rice lines
- Sense OsCDPK13 transgenic rice lines
- dwarf mutants of rice：
To further test the correlation between the level of OsCDPK13 expression and plant height, OsCDPK13 protein levels were analyzed in dwarf mutants of rice.
The expression of OsCDPK13：
- OsCDPK13 was detected in the cytosolic fraction, but not in the membrane fraction, showing that OsCDPK13 is a cytosolic protein. OsCDPK13 was undetectable in cytosolic fractions from root, leaf blade, and anthers.
- OsCDPK protein accumulates predominantly in callus and in leaf sheath of young seedlings.
- Os-CDPK13 has protein kinase activity and that this activity was increased by cold and GA.
- Leaf sheath OsCDPK13 mRNA levels were increased by GA3 treatment, unaffected by BL, and suppressed by ABA.
- OsCDPK13 mRNA abundance in leaf sheath was increased by cold treatment and suppressed by salt and drought treatment
- OsCDPK13 was up-regulated in response to GA3 treatment, but suppressed in response to ABA and BL, which suggesting that OsCDPK13 may act downstream of a GA-induced Ca2+ influx during elongation of rice leaf sheath.
- OsCDPK13 expression increased in response to low temperature, suggesting a role for this protein in the response to cold stress.
- Overexpression of OsCDPK13 can protect plants from cold damage.
- OsCDPK13 has a high level of identity with three other rice CDPKs, namely OsCDPK1 (AY158077), OsCDPK11(X81393) and OsCDPK12(AF048691). These four rice CDPKs are located within 7.6 cM of rice chromosome number 3, suggesting that they may all arise from the same gene by alternative splicing of mRNA. However, it was not known whether these increases in mRNA levels were accompanied by increases in protein levels and/or kinase activity.
- The phylogenetic tree was created using the ClustalW program based on the alignment of the kinase catalytic domains of 29 rice (OsCPK1-OsCPK29) and 34 Arabidopsis (AtCPK1-AtCPK34) CDPKs. OsCPK21 is indicated by an arrow. Phylogenetic analysis showed that rice CDPKs are divided into four distinct classes(Fig. 1).
OsCPK13 (OsCDPK7) belongs to the Group I.
- To study the evolutionary relatedness of rice and Arabidopsis CDPKs with all the CDPK genes characterized so far from alfalfa, cucumber, ice plant, mung bean, potato, strawberry, tomato, Petunia, maize, tobacco and Medicago, an unrooted tree was constructed by using ClustalX 1.83. This exercise resulted in four distinct groups similar to that reported by Asano et al.(Fig. 2).
- The amplitude of difierential expression for these genes was not as significant as reported earlier, possibly due to use of difierent rice variety and/or experimental conditions. Most of the previously identiWed stress responsive CDPK genes cluster together in
subclades Ia and Ib(Fig. 2).
- Each calcium-dependent protein kinase (CDPK) consists of a variable N-terminal domain, a protein kinase domain, an autoinhibitory region and a calmodulin-like domain with EFhand Ca2+-binding sites. CDPKs are directly activated by the binding of Ca2+ to the calmodulin-like domain, and the activated CDPKs regulate downstream targets. CDPKs have been identified throughout the plant kingdom， and in some protozoans, but not in animals. CDPKs constitute a large multigene family in various plant species; CDPK genes have been identified in Arabidopsis thaliana, and CDPK genes have been found in Oryza sativa (rice) (Fig. 3). The expression and activities of CDPKs are upregulated by a variety of stimuli, such as hormones, abiotic stresses and biotic stresses. Red letters indicate CDPKs involved in abiotic stress signaling.
- Phylogenetic relationships among rice CCaMK, and rice and Arabidopsis CDPKs, CRKs and PEPRKs. A phylogenetic tree was created using the ClustalW program, based on the predicted amino acid sequences of the rice and Arabidopsis kinases, which are indicated by red and blue type, respectively.As shown in Fig. 4, the phylogenetic tree of these kinase sequences forms seven subgroups: CDPKs I–IV, CRKs, CCaMK and PEPRKs. Furthermore, the 29 rice CDPKs were divided into four distinct classes.
- In rice, the CDPKs constitute a large family of 29 genes.
- CDPK genes (OsCPK1-29) contain multiple stress-responsive cis-elements in the promoter region (1 kb) upstream of genes. Analysis of the information extracted from the Rice Expression Database indicates that 11 of the CDPK genes are regulated by chilling temperature, dehydration, salt, rice blast infection and chitin treatment. RT-PCR and RNA gel blot hybridization were performed in this study to detect the expression 19 of the CDPK genes. Twelve CDPK genes exhibited cultivar- and tissue-specific expression; four CDPK genes (OsCPK6, OsCPK13, OsCPK17 and OsCPK25) were induced by chilling temperature, dehydration and salt stresses in the rice seedlings. While OsCPK13 (OsCDPK7) was already known to be inducible by chilling temperature and high salt, this is the first report that the other three genes are stress-regulated. OsCPK6 and OsCPK25 are up-regulated by dehydration and heat shock, respectively, while OsCPK17 is down-regulated by chilling temperature, dehydration and high salt stresses. Based on this evidence, rice CDPK genes may be important components in the signal transduction pathways for stress responses.
- Three major classes of Ca2+-binding proteins have been characterized in higher plants: calciumdependent protein kinases (CDPKs), calmodulins (CaMs) and CaM-like proteins, and calcineurin B-like proteins.
- The subcellular localization of each CDPK and the phenotypes of overexpression (OX) or knockout or knockdown (KO) lines are described. Red letters, Arabidopsis CDPKs; green letters, rice CDPKs; P, phosphorylation; ABF, ABA-responsive element binding factor; HSP1, a heat shock protein; OST1, open stomata 1 protein kinase(Fig. 5).
Labs working on this gene
- National Institute of Agrobiological Sciences, Tsukuba 305-8602, Japan
- National Institute of Crop Science, 2-1-18 Kannondai, Tsukuba 305-8518, Japan
- National Agricultural Research Center for Tohoku Region, Akita 014-0102, Japan
- ↑ 1.0 1.1 1.2 1.3 1.4 1.5 1.6 1.7 Abbasi F, Onodera H, Toki S, et al. OsCDPK13, a calcium-dependent protein kinase gene from rice, is induced by cold and gibberellin in rice leaf sheath[J]. Plant molecular biology, 2004, 55(4): 541-552.
- ↑ 2.0 2.1 2.2 Asano T, Hakata M, Nakamura H, et al. Functional characterisation of OsCPK21, a calcium-dependent protein kinase that confers salt tolerance in rice[J]. Plant molecular biology, 2011, 75(1-2): 179-191.
- ↑ 3.0 3.1 3.2 Ray S, Agarwal P, Arora R, et al. Expression analysis of calcium-dependent protein kinase gene family during reproductive development and abiotic stress conditions in rice (Oryza sativa L. ssp. indica)[J]. Molecular Genetics and Genomics, 2007, 278(5): 493-505.
- ↑ 4.0 4.1 4.2 4.3 Asano T, Tanaka N, Yang G, et al. Genome-wide identification of the rice calcium-dependent protein kinase and its closely related kinase gene families: comprehensive analysis of the CDPKs gene family in rice[J]. Plant and cell physiology, 2005, 46(2): 356-366.
- ↑ 5.0 5.1 5.2 5.3 Asano T, Hayashi N, Kikuchi S, et al. CDPK-mediated abiotic stress signaling[J]. Plant Signal Behav, 2012, 7(7): 817-821.
- ↑ 6.0 6.1 Wan B, Lin Y, Mou T. Expression of rice Ca< sup> 2+</sup>-dependent protein kinases (CDPKs) genes under different environmental stresses[J]. FEBS letters, 2007, 581(6): 1179-1189.