BIOD27H3 Study Guide - Insulin-Like Growth Factor 1 Receptor, Igfbp3, Insulin Receptor
18 Dec 2012
School
Department
Course
Professor
Document Summary
Is a hormone with molecular structure similar to insulin. Plays imp role in childhood growth and continues to have anabolic effects in adults. 70 aa in a single chain with 3 intramolecular disulfide bridges. Produced by liver as a endocrine hormone (also by target tissues) Can be retarded by under nutrition, gh insensitivity etc. Most dominant form is bound: with binding proteins, most dominant bp: igf-bp3. Igf-1 potent activator of akt signaling pathway, a stimualtor cell growth and proliferation. Binds to atleast 2 cell surface receptors: igf-1 and the insulin receptor. Igf-1r is the physio receptor- binds igf-1 with higher affinity than insulin receptor. Igf-1r is also tyrosin kinase receptor like insulin receptor. Other igfbp"s are inhibitory, i. e igfbp-2 and igfbp-5. Increase in serum levels of these 2 igfbps result in a decrease in igf-1 activity. Deficiency in gh or igf-1 leads to diminished stature.
