Abstract:

To study the structure，function and expression patterns of CDPK（calcium-dependent protein kinase）genes in Dendrobium officinale Kimura et Migo，cDNA sequences were cloned from Dendrobium officinale by RACE and RT-PCR. The full length of cDNA sequences of DoCDPK1 and DoCDPK2 geneswere 1 863 bp and 1 729 bp which the ORF（open reading frames）were 1 539 bp and 1 536 bp encoded 512 and 511 amino acids，respectively. And DoCDPK1 and DoCDPK2 proteins were hydrophilic and stable，whose secondary structures were made up of α-helix and random coil. The qRT-PCR analysis showed that DoCDPK1 and DoCDPK2 genes mainly expressed in leaves. The expression of DoCDPK1 and DoCDPK2 genes increased under low temperature and NaCl. However，the expression of DoCDPK1 and DoCDPK2 genes showed different expression patterns under the treatment of ABA. We speculated that DoCDPK genes took part in the abiotic stress like cold stress. The results will lay the foundation of further study of the specific regulation mechanism and relationship with other signaling pathways.

Key words: Dendrobium officinale, CDPK, gene cloning, abiotic stress, gene expression