Resisting Cell Death W6

Question 1

P53 also induces apoptosis. How

Answer 1

When DNA damage is detected, p53 is activated and can halt the cell cycle to allow repair. If the damage is irreparable, p53 can trigger apoptosis by activating pro-apoptotic genes.

Question 2

Normal P53 vs abnormal

Answer 2

• Normal p53 protein destroys cells that have irreparable damage to their DNA
• Abnormal p53 fails to stop cell division, damaged cells divide, cancer develops

Question 3

What causes genomic instability?

Answer 3

• Loss or mutation of the DNA damage sensor protein p53
• Breakdown in one or more DNA repair mechanisms (e.g. DNA mismatch repair, base excision repair)
• Mutagenic agents and viruses
• A combination of these factors

Question 4

strategies to resist cell death (5)

Answer 4

1. Overexpression of Anti-Apoptotic Proteins
2. Inactivation of Pro-Apoptotic Proteins
3. Mutations in the p53 Tumor Suppressor Gene
4. Activation of Survival Signaling Pathways
5. Overexpression of Inhibitors of Apoptosis Proteins