BIOB11H3 Lecture Notes - Tumor Suppressor Gene, Oncogene, Cell Adhesion
Document Summary
Bio b11 lec 20-21 c16 proto-oncogenes, oncogenes, and tumor suppressor genes. Tumor suppressor gene: - gene that controls protein that controls expression. 1 copy of the tsg is enough for it to take effect. Must have 2 mutations to have control by mutation (mutation is recessive). Fig 16-8: (a): effects of mutations in tumor suppressor genes. Both copies of a tsg must be knocked out to cause it to lose growth control. Tsg"s suffer loss-of-function mutations and/or epigenetic inactivation that render them unable to restrain cell growth. mutation in one of 2 copies (alleles) of an oncogene may be sufficient to cause a cell to lose growth control. Oncogenes arise from proto-oncogenes as the result of gain-of-function mutations, that is, mutations that cause the gene product to exhibit new functions that lead to malignancy. Fig 16-8 (b): contrasting effects of mutations in oncogenes. In a normal hybrid, normal growth control is re-established deleted is between regions q11. 21 & q21. 2!
