Comparative sequence-structure analysis of Aves insulin.

Normal blood glucose level depends on the availability of insulin and its ability to bind insulin receptor (IR) that regulates the downstream signaling pathway. Insulin sequence and blood glucose level usually vary among animals due to species specificity. The study of genetic variation of insulin, blood glucose level and diabetics symptoms development in Aves is interesting because of its optimal high blood glucose level than mammals. Therefore, it is of interest to study its evolutionary relationship with other mammals using sequence data. Hence, we compiled 32 Aves insulin from GenBank to compare its sequence-structure features with phylogeny for evolutionary inference. The analysis shows long conserved motifs (about 14 residues) for functional inference. These sequences show high leucine content (20%) with high instability index (>40). Amino acid position 11, 14, 16 and 20 are variable that may have contribution to binding to IR. We identified functionally critical variable residues in the dataset for possible genetic implication. Structural models of these sequences were developed for surface analysis towards functional representation. These data find application in the understanding of insulin function across species.