Explain

Part III. Short Answers (9 points each question, 36 points total). You must answer four of the following six short answer questions. Please answer only 4 questions. If you answer more, I will only take your first 4 (i.e. I won't take your best 4). 1. Describe the relationship between Rb and p53 regarding regulating apoptosis. You may draw a diagram as part of your answer, but you still must explain your answer. What is the impact of DNA damage on regulating p53 and what factor(s) are directly responsible? How does p53 impact the pro-survival signaling of IGF-17 Kim Fear Rb -EQF - ARF-MDM2-1P53 - IGFBP-3- IGF-1, IOF. 2 The decsion for apoptosis starts w/ Rb which is a regulator of EXF. However, when hyper phosphorylated, Ro no longer is able to inhibit ELF which means now It can act as a potent tran factor with a variety of favorite targets; one such being ARF. ARF acts to inhibit the ubiquitin- ligase activity of MOMZ by Phosphorylating it. When Phosphorylated, MOMZ is no longer able to bind DEZ and tug it for ubiquilation (proteolytic degradation). This means P53 is now free to make the decision to undergo apoptosis. Such extrinsic factors ( happening outside the environment of the cell ) such as UV exposure resulting in DNA damage (.. c. double - stranded breaks) also affect P63's decision in finalizing apoptosis and signaling downstream affects (such as caspase, Ead, Bak, etc activity ) leading to apoptosome formation, Pro- survival signals also affect P53: you example IGF- 1 and IGF- 2 ( which are insulin growth factors) may end mattered to IGFBP - 3 resulting in a decision fe meave, however, pas