Expression Analysis of ZmCDPK9 Gene in Maize under Abiotic Stress

【 Objective 】 Calcium dependent proteinkinases (CPKs), a kind of serine/threonine protein kinases, are only found in plants and lower animals. Ca²⁺, as a second messenger, plays important roles in various aspects of plant physiology and is involved in many cellular processes. The purpose of this paper is to study the dynamic expression of ZmCPK9 gene in seedling stage under different stress conditions and to lay the foundation for further analysis of the function and mechanism of this gene in maize adverse stress response.【 Method 】ZmCPK9 gene sequence features were analyzed by using bioinformatics methods, and the expression characteristics of ZmCPK9 under drought, low temperature, salt and ABA stress were analyzed by real-time PCR technique. 【 Result 】The sequence analysis showed that ZmCPK9 had a length of 1,548 bp in the genome, encoding 515 aminoacids residues. Bioinformatics analysis revealed that the protein sequence and structure of the ZmCPK9 gene were as conservative as those of other species, the CPK gene. Real-time PCR analysis discovered that the expression of ZmCPK9 was up-regulated by ABA, cold, drought and salt stress, respectively. 【 Conclusion 】ZmCPK9 is a new member in corn CPKs gene family in maize. The gene is involved in signal transduction regulation under the condition of drought, low temperature, salt, and ABA stress. We speculate ZmCPK9 has a certain role in plant defense under abiotic stress.