Anatomy and Cell Biology 4429A Lecture Notes - Lecture 13: P16, Missense Mutation, Oncogene
Document Summary
Oncogenes vs. tumor-suppressor genes: oncogenes arise from mutations of proto-oncogenes (normal versions) that normally positively regulate cell growth and proliferation. They predispose to oncogenic transformation, are dominant, and are associated with gain-of-function mutations. C-raf (cell growth regulation: tumor-suppressor genes code for proteins that inhibit cell growth and proliferation; inactivation leads to tumor development. The are recessive or dominant-negative and are associated with loss-of-function mutations. P16 (e(cid:374)sures the (cid:272)ells do(cid:374)"t e(cid:374)ter (cid:373)itosis(cid:895) Src is a kinase that had the ability to create sarcomas. If you transfer these viruses from one chicken to another, it created sarcomas. Turns out v-src was a viral version of the cellular c-src. Through evolutionary studies it was found that humans always had c-src. They were never initially intended to be oncogenic. Additionally, remember that rna viruses cannot infect non-dividing cells. Now that they have mutated the src protein, they force the cell to go through cell division. Instead of targeting oncogenes, these viruses target tumor suppressors.