Identification of a novel Gig2 gene family specific to non-amniote vertebrates.

Identification of a novel Gig2 gene family specific to non-amniote vertebrates.

Blog Article

Gig2 (grass HEMO FACTORS carp reovirus (GCRV)-induced gene 2) is first identified as a novel fish interferon (IFN)-stimulated gene (ISG).Overexpression of a zebrafish Gig2 gene can protect cultured fish cells from virus infection.In the present study, we identify a novel gene family that is comprised of genes homologous to the previously characterized Gig2.EST/GSS search and in silico cloning identify 190 Gig2 homologous genes in 51 vertebrate species ranged from lampreys to amphibians.Further large-scale search of vertebrate and invertebrate genome databases indicate that Gig2 gene family is specific to non-amniotes including lampreys, sharks/rays, ray-finned fishes and amphibians.

Phylogenetic analysis and synteny analysis reveal lineage-specific expansion of Gig2 gene family and also provide valuable evidence for the fish-specific genome duplication (FSGD) hypothesis.Although Gig2 family proteins exhibit no significant sequence similarity to any known proteins, a typical Gig2 protein appears to consist of two conserved parts: an N-terminus that bears very low homology to the catalytic domains of poly(ADP-ribose) Wiring Harness polymerases (PARPs), and a novel C-terminal domain that is unique to this gene family.Expression profiling of zebrafish Gig2 family genes shows that some duplicate pairs have diverged in function via acquisition of novel spatial and/or temporal expression under stresses.The specificity of this gene family to non-amniotes might contribute to a large extent to distinct physiology in non-amniote vertebrates.