Bioinformatics and Molecular Modeling of the Camel Insulin Receptor

Abstract

Camels are well known for their high blood glucose content and marked glucose tolerance. In order to understand the glycemic control in camels the role of insulin receptor was investigated. The camel insulin receptor sequence, structure model, and domain content were compared with those of humans and other vertebrates. The results indicated 100% identity rate in old world camels, 99.7% identity rate with new world camels and 96% with humans. There was a high identity rate among insulin receptors in domestic animals (82.3–100%). Despite the conserved features of the insulin 1 binding site (the main functional insulin molecules), the second insulin-binding site in camel insulin receptors showed interesting differences. Most of the sequence differences between human and camel insulin receptors were concentrated in the insertion domains (ID), particularly the ID-β loop. ID-α′∼αCT′∼ID-β, which is important for insulin receptor signal transduction, showed a greater positive electrostatic potential in camels. Such differences might be associated with the noticed hyperglycemia and insulin resistance in camels by affecting the movement of the α-CT helix which lies between the IDs and signifcantly affects the main insulin molecules, lowering the affnity at insulin site 1 and by affecting the transmission of the insulin signal to the intracellular domain.