Molecular cloning and expression of the mitochondrial 60-kDa heat shock protein from an arctic copepod Calanus glacialis

Abstract

Heat shock proteins (Hsps) play an essential role in cell defense against cell damages by several environmental and physiological stresses. We cloned and sequenced full-length heat shock protein 60-kDa (Hsp60) from the Arctic copepod Calanus glacialis cDNA. The complete nucleotide sequence of Calanus glacialis Hsp60 (Cg Hsp60) gene contained 2,092 bp in length. The open reading frame (ORF) was 1,743 bp flanked by a 5'-UTR of 90 bp and a long 3'-UTR of 259 bp, and encoded a putative protein of 581 amino acids with a calculated molecular weight of 62 kDa. It showed high similarity to those of Culicoides variipennis (73%), Aedes aegypti (72%), and Tribolium castaneum (71%) at the amino acid sequence level. In phylogenetic analysis, it clustered with other arthropods sequences. We also confirmed that the recombinant protein of C glacialis Hsp60 by the SDS-PAGE and immunoblotting analysis after expression of recombinant gene construct in Escherichia coli.