Expression of rice Ca²⁺‐dependent protein kinases (CDPKs) genes under different environmental stresses

Abstract

Ca 2+ -dependent protein kinases (CDPKs) play an essential role in plant Ca 2+ -mediated signal transduction. Twenty-nine CDPK genes have been identified in the rice genome through a complete search of genome and full-length cDNA databases. Eight of them were reported previously to be inducible by different stress stimuli. Sequence comparison revealed that all 29 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. Findings from this research are important for further dissecting mechanisms of stress response and functions of CDPK genes in rice.

Expression Profiling of a Novel Calcium-Dependent Protein Kinase Gene,LeCPK2, from Tomato (Solanum lycopersicum) under Heat and Pathogen-Related Hormones

“…19,20) In this study, LeCPK2 expressed widely in different organs, but an enhanced accumulation of mRNAs was detected in the flowers, suggesting that LeCPK2 has a broad range of functions during plant growth and development, especially in reproductive growth. The expression profile of LeCPK2 in tomato organs was similar with that of tobacco NtCPK4, an ortholog of LeCPK2, which expressed in the roots, stems, leaves and flowers, especially a high expression in the flowers, according to Zhang.…”

Plant drought stress: effects, mechanisms and management

“…Both abscisic aciddependent and -independent osmotic stress signaling first modify constitutively expressed transcription factors, leading to the expression of early response transcriptional activators, which then activate downstream stress tolerance effector genes (Zhu, 2002). Recently, Wan et al (2007) reported that amongst the 29 calcium-dependent protein kinase genes identified so far, all contained multiple stress-responsive cis-elements upstream in the promoter region (1 kb). Sucrose non-fermenting 1-related protein kinase 2 has also been reported to be capable of mediating signals initiated during drought stress, resulting in appropriate gene expression (Umezawa et al, 2005).…”

Humic matter elicits proton and calcium fluxes and signaling dependent on Ca2+-dependent protein kinase (CDPK) at early stages of lateral plant root development

“…We also evaluated the expression of two CDPK genes, OsCPK7 and OsCPK17, both constitutively expressed in roots, stems, leaves, and panicles and responsive to various stress stimuli [33]. OsCPK7 was upregulated by salt stress in roots [33], jasmonic acid [34], cold, and gibberellin [35] and suppressed by rice blast infection [33]. OsCPK17 is downregulated by cold, drought, and salt stress in the rice seedlings [33].…”

“…Sperandio et al [29] showed that OsA7 is upregulated in response to nitrogen resupply and suggested that OsA7 could be involved in N nutrition in rice. We also evaluated the expression of two CDPK genes, OsCPK7 and OsCPK17, both constitutively expressed in roots, stems, leaves, and panicles and responsive to various stress stimuli [33]. OsCPK7 was upregulated by salt stress in roots [33], jasmonic acid [34], cold, and gibberellin [35] and suppressed by rice blast infection [33].…”