Abstract

A full-length cDNA sequence coding for calcium-dependent protein kinase of mulberry tree, which we designated was MCDPK and this was cloned based on mulberry expressed sequence tags (ESTs). Sequence analysis showed that the MCDPK is 2249 base pairs in length, encoding 532 amino acids with a predicted molecular weight of 59.96 kDa and an isoelectric point of 6.84. The mRNA expression level ofMCDPK at different developmental stages in mulberry leaves and flowers and in different tissues was investigated. The results showed that MCDPK transcripts were most abundantly expressed in the terminal bud, and the expression level of the mRNA was reduced significantly under the conditions of low temperature and salt stress when compared to the normal growth environment. The findings of the study laid the foundation for understanding the resistance mechanism of functional genes in mulberry in the future.

Key words: Mulberry, calcium-dependent protein kinase gene (CDPK), gene cloning, abiotic stress, gene expression.