Question

Excessive Myc production leads to the rpoduction of p19ARF, which binds to Mdm2 and frees p53, allowing it to be more easily phosphorylated. The stable p53 then goes onto induce cell-cycle arrest or apoptosis.

Answer 1

P53 is a multi-functional protein that regulates the cell cycle by detecting DNA damage and anomalies during the G₁ phase. It can halt the cell cycle and recruit enzymes for DNA repair, or trigger apoptosis if the DNA damage cannot be repaired.

Step-by-step explanation:

P53 is a multi-functional protein that plays a critical role in regulating the cell cycle. When there is DNA damage or other anomalies detected in cells during the preparatory processes of the G₁ phase, p53 halts the cell cycle and recruits enzymes for DNA repair. If the DNA damage cannot be repaired, p53 can trigger apoptosis, or cell death, to prevent the duplication of damaged chromosomes. The levels and activity of p53 are controlled by other proteins, such as Mdm2 and p21, which impact the cell's response to cell cycling anomalies and determine whether the cell undergoes cell-cycle arrest or apoptosis.