BIOL 4015 Chapter Notes - Chapter 5: Spindle Checkpoint, G1 Phase, G2 Phase
Document Summary
Chapter 5 the cell cycle: cancer is characterized by abnormal cell proliferation which involves reproduction of cell to form 2 daughter cells. Association with cyclins: binding of cyclins to cdk causes conformational change in cdk that allows binding of protein substrate and correct positioning of atp. Inactive cdk molecule has conformation that blocks binding of protein substrate and correct alignment of atp: ubiquitin ~ small polypeptide, covalent addition of to lysine amino acids of cyclin flags of protein for degradation by proteasome. Association with inhibitors: cyclin cdk activity is regulated by, p16 (ink) family, bind cdks 4/6 and interfere with binding of cdks 4/6 to cyclin d, p21 (cip/kip) family. Inhibitors that interact with both cyclins and their associated cdks and block atp binding site to disable kinase activity. 5. 3 progression through g1 checkpoint: rb protein tumor suppressor protein; molecular link for g1-s phase transition, doesn"t bind to specific dna sequences but regulates activity of e2f tf family.
