Cloning and sequence analysis of calcium-dependent protein kinase gene in sugarcane

ObjectiveThe calcium-dependent protein kinase gene in sugarcane(ScCDPK1) was cloned to provide re-ferences for revealing its biological functions and further utilization in breeding. MethodThe specific primers were de-signed according to known CDPK gene sequence from sugarcane cDNA library. ScCDPK1 gene was cloned using RT-PCR. The physical and chemical properties, transmembrane domain, signal peptide, and conserved domains were analyzed using online bioinformatics algorithms. ResultThe full coding sequence of ScCDPK1 gene was cloned, which included 1650 bp in length and encoded 549 amino acid residues. Its relative molecular weight was 61.971 kD, isoelectric point(pI) 6.78 and instability index 35.63. Homology and phylogenetic tree analysis showed that ScCDPK1 of sugarcane shared the closest ge-netic relationship with TaCPK7 of wheat and had 88%similarity. Like other known CDPK proteins, ScCDPK1 protein con-tained four conserved domains(variable domain, protein kinase domain, self-inhibition domain and calcium binding do-main). Its protein secondary structure mainly consisted of alpha helix (42.80%) and random coil (32.97%). Protein func-tional analysis showed that ScCDPK1 protein was a kind of cation channel protein which play important roles in many biology processes such as plant stress response, signal transduction and translation. ConclusionLike other known CDPK proteins, the protein encoded by ScCDPK1 gene contains four conserved domains which is peculiar to CDPKs family. And it is a cation channel protein.