Question

What gene discussed in this chapter might be responsible for pausing the cell cycle of dividing cells long enough for radiation-induced damage to be repaired in cells?

Answer 1

The p53 gene is responsible for pausing the cell cycle at the G₁ checkpoint to allow for DNA repair or to trigger apoptosis if repair is not possible.

Step-by-step explanation:

The gene responsible for pausing the cell cycle in dividing cells to allow for the repair of radiation-induced damage is the p53 gene. This protein plays a crucial role at the G₁ checkpoint of the cell cycle. When DNA damage is detected, p53 halts the cell cycle and recruits specific enzymes to repair the DNA. Moreover, if the DNA damage cannot be repaired, p53 can trigger apoptosis, or programmed cell death, to prevent the spread of damaged chromosomes. The protein p21 is also involved, as it enforces the halt in the cell cycle dictated by p53 by binding to and inhibiting the activity of the Cdk/cyclin complexes.