Molecular characterization and gene expression of insulin like growth factor 1 (IGF-1) in etroplus suratensis (pearlspot)

Insulin like growth factor- 1 (IGF-1) plays main role in the overall growth and development of all vertebrates including fish. Besides contributing for somatic growth the IGF-1 gene is entitled with having other numerous pleiotrophic functions including role in reproduction, osmoregulation, immunity, and many more. The molecular characterization of IGF-1 gene in Etroplus suratensis was taken up because of the increasing commercial value of the species. In the present study we have amplified and sequenced the IGF-1 gene of E. suratensis. The sequence exhibited 91.47% similarity to Oreochromis niloticus IGF-1 gene. We also analysed the relative expression of IGF-1 gene in different tissues like brain, eye, gills, gonads, heart, intestines, kidney, liver, muscle and spleen. All the tissues were positive for the IGF-1 expression. The RT-PCR demonstrated that IGF-1 expression was higher in liver, spleen, eye, gonads and brain followed by low expression in intestine, kidney, heart and gills.To our knowledge this is the first report on the characterization an expression analysis of insulin like growth factor 1 (IGF-1) of E.suratensis. The IGF-1 characterized in this study can be used as a molecular marker for further genetic improvement of the species.