Cloning and expression of DnaJ homolog in carrot somatic embryo*

Abstract

Abstract As the co-chaperone of DnaK/Hsp70 protein, DnaJ/Hsp40 protein influences the synthesis and assembly of the protein complex by regulating ATPase activity of DnaK/Hsp70 protein. By employing the modified method of cDNA representational difference analysis, a homologous fragment of DnaJ was isolated from the deregulated carrot somatic embryos and it was further used as the probe to screen the cDNA library of carrot somatic embryo deregulated for 12 h. As the result. DcJ1 gene, the homologous gene of DnaJ, was isolated from carrot. Sequence analysis showed that its coding region is 1257 bp, which codes 418 amino acids and comprises 3 highly-conserved characteristic domains. Southern blot analysis suggested that the DcJ1 gene seems to be a single copy in the genome, while Northern blot result indicated that DcJ1 expresses only in roots and its degree of expression changes obviously with the regulation-deregulation process. These results suggest that DcJ1 is correlated with the early development of car...