Characterization, physical location and expression of the genes encoding calcium/calmodulin-dependent protein kinases in maize (Zea mays L.)

The maize genomic sequence and cDNA encoding a calcium/calmodulin-dependent protein kinase homolog were isolated and identified. The deduced peptide ( MCK2) from this cDNA shared high amino acid identity (91.2%) with maize MCK 1. These two genes were physically mapped onto chromosomes by fluorescence in situ hybridization using the first introns of the genes as gene-specific probes. While the MCK1 gene was assigned to a locus on the long arm of chr omosome 9, the MCK2 gene was localized to a locus on the long arm of chromo some 1. Both of these genes were expressed in roots, leaves, stems and flow ers, and the expression patterns of MCK were verified by RNA in situ hybrid ization. These results indicated that MCK expression is temporally and spat ially regulated during maize growth and development.