Journal of Fisheries and Life Sciences

Author(s): Sivaraman Balasubramanian, Renuka Vijayakumar, Elavarasan Krishnamoorthi and Shanmughavel Piramanayagam

Abstract: Polypeptides which synthesized in cell are more prone to interact with the cellular components that may lead to undesirable folding functions. This situation is taken care of a group of molecules called Heat shock proteins (Hsps) come under molecular chaperons. They play -several important roles such as processing of newly synthesized polypeptides into functional native conformation, prevention of degradation of polypeptides, translocation of newly synthesized polypeptides across the membrane and maintaining the homeostasis of protein under stress conditions in an organism. Among Heat shock proteins, Hsp70and DnaJ proteins are well established molecular chaperon machinery for their various cellular functions. Binding of Hsp70s with substrate polypeptides for executing any functions are associated with an ATP hydrolysis cycle and- induced by DnaJ/ Hsp40 family. Knowledge of the correct phylogenetic relationship among vertebrates is crucial for the valid interpretation of evolutionary trends in DnaJ proteins. In the present computational analysis, identification and systematic classification of DnaJ proteins using genome wide analysis of zebrafish(Danio rerio) has been outlined. Phylogenetic analysis of DnaJ protein from five fish models, Danio rerio, Takifugu rubripes, Oryzias latipes, Gasterosteus aculeatus and Tetraodon nigroviridis reveal that a close relationship prevails between fugu and tetraodon, medaka and stickleback. Whereas zebrafish have shown independent evolution. Apart from phylogenetic analysis a comprehensive domain structural organisation, sub cellular localization and gene distribution of zebrafish DnaJ proteins have also been documented.