[Cloning and characterization of Hsp70a cDNA fragment of Dunaliella salina].

The present study is to obtain heat shock protein 70a cDNA fragment from Dunaliella salina. Two pairs of degenerate primers were designed according to conserved motifs of DIDLGTT,DQGNRTTP,PAYFNDS and ATKDAG of the homologous amino acid sequences and used to amplify hsp70a cDNA fragment from heat-shock-treated Dunaliella salina by nest PCR technique. The resulting PCR products were inserted into T-vector then transformed into JM109. Ten colonies were selected to determine their sequences. Homologous analysis of the deduced amino acid sequences were performed by BLAST and subsequently compared with GenBank data. Three of ten nucleotide sequences were obtained,of which there was 372 bp coding 126 amino acids. The sequences shared high homology with hsp70a,with identity 96% to Chlamydomonas reinhardtii, 94% to Petunia, 93% to Pisumsativum, 92% to tomato, 92% to human,90% to Drosophila and 89% to yeast respectively. It can be concluded that the cloned sequence is putatively hsp70a cDNA fragment from Dunaliella salina.