p53 gene product is a tumour suppressor that is present in low amounts in cytoplasm in undamaged DNA and activated via signal in damaged DNA and transcribed in nucleus

Mutations in p53 gene or its regulation are the most common changes in cancer. Activated p53 controls the decision to:

Divide- ignore damage and enter S phase
Arrest- pause cycle and repair damage
Die- apoptosis if damage is too severe

Role of p53:

Promotes expression of Cdki (cyclin dependent kinase inhibitor)- p21
p21 inhibits cyclin E and A/Cdk- preventing entry to S
p21 inhibits PCNA - halts ongoing respiration

	Created by Chloe Cavarretta over 5 years ago

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