ANSC 3316 Lecture Notes - Lecture 8: Insulin Receptor, Dna Replication, Proinsulin
Document Summary
Igf insulin-like growth factor: igf i. Bovine, porcine, and human igf i are identical. Bovine & human differ by 3 amino acids. Pre-natal growth: structure is very similar to that of pro-insulin (precursor molecule to insulin) Insulin has a c-peptide that igf does not have; otherwise they"re the same. Tyrosine kinase (hormone binds, conformational shift, kinase activity) Each hormone can bind to the other receptor. Insulin can bind to igf receptor: igf receptors (prenatally) Igf type i receptor mediates most activity of igf i and igf ii. Igf type ii receptor may act as sink for excess igf ii (regulates how much igf ii is available to fetus) Serves to regulate how much igf ii is in circulation. Animals die, but are much larger than they are in the type i deficiency. Too much igf ii in circulation results in death (too much igfii is detrimental) Igf-i receptor has its own kinase, phosphorylation of itself initiates cascade: igf in bone.
