Characterization of two insulin-binding components of rat-liver plasma membranes.
We have identified and isolated two forms of insulin receptor from rat-liver plasma membranes. The smaller (Mr = 90k) is a single polypeptide. The same polypeptide appears to be the insulin-binding site of the larger Mr = 280k). Only the larger, multisubunit, receptor shows high-affinity binding of insulin and negative cooperativity in its dissociation kinetics.
D000818:Animals; D002462:Cell Membrane / Q000378:metabolism; D007328:Insulin / Q000031:analogs & derivatives / Q000378:metabolism; D007700:Kinetics; D008099:Liver / Q000378:metabolism*; D008970:Molecular Weight; D051381:Rats; D011972:Receptor, Insulin / Q000302:isolation & purification / Q000378:metabolism*
D007328:Insulin; C008147:insulin, iodo-; D011972:Receptor, Insulin