How does the presence of a p53 mutation affect the cell cycle?

The presence of a p53 mutation primarily leads to uninterrupted cell cycle progression. The p53 protein functions as a critical tumor suppressor that monitors the integrity of the cell's DNA and regulates the cell cycle. Under normal conditions, p53 can halt the cell cycle in response to DNA damage, allowing time for repair or triggering apoptosis (programmed cell death) if the damage is irreparable.

When p53 is mutated, its ability to perform these functions is compromised. This failure means that damaged cells can continue to divide unchecked, leading to problems like genetic instability and potentially cancerous growth. In this context, "uninterrupted cell cycle progression" refers to the ability of the cell to continue through the cell cycle phases without the necessary checkpoints that would normally be activated by functional p53.

This understanding underscores the importance of p53 in maintaining normal cell cycle regulation and highlights its role in preventing tumor formation.