Chapter 11.2, Problem 4R

Summary Introduction

To analyze:

The implication of the presence of p16 protein in the cells of the old people and aging.

Introduction:

p21 is a protein that is involved in regulating the G (gap) 1 checkpoint. When the DNA (deoxyribonucleic acid) in the cell is damaged, it leads to the production of p21 protein. This protein interacts with the G1-S (synthesis) Cdk, thereby, preventing the binding of the cyclin protein. The inactivated Cdk then leads to the halting of the cell cycle for repair. When the damage is more, the cell undergoes apoptosis. The protein p21 is similar to the p16 protein and have the similar function. The p16 protein is more in the old people than in the young people.