Hagfish insulin: the discrepancy between binding affinity and biologic activity.
Hagfish insulin exhibits a binding affinity of about 25% of that of pig insulin in rat adipocytes and IM-9 lymphocytes, even though its relative biologic potency is only about 5% in adipocytes. The dissociation rate constant of hagfish insulin is about half that of pig insulin, and the association rate constant is about one eighth. A longer time is, therefore, required for hagfish insulin to reach a steady state of binding. Failure to reach steady state is the probable reason why some previous results suggested a relative binding affinity of hagfish insulin of the same magnitude as the relative biologic potency.
D000273:Adipose Tissue / Q000378:metabolism*; D000818:Animals; D001667:Binding, Competitive; D005399:Fishes / Q000378:metabolism*; D006196:Hagfishes / Q000378:metabolism*; D007328:Insulin / Q000378:metabolism*; D007700:Kinetics; D008214:Lymphocytes / Q000378:metabolism; D011972:Receptor, Insulin / Q000378:metabolism*; D013045:Species Specificity; D013552:Swine
D007328:Insulin; D011972:Receptor, Insulin