Question

The p53 tumor suppressor gene was isolated from a tumor where p53 protein levels were very high. This was likely due to dominant-acting mutant that inactivated all p53 tetramers and blocked the tumor suppressing effects of wild type p53.

true or false

Answer 1

Answer: TRUE
Explanation:
Proto-oncogenes genes promote cell proliferation.
i.e. they are activators of cell division.

Tumor suppressor genes inhibit cell proliferation.
i.e. they are repressors of cell division.

Loss of function mutations in tumor suppressor genes lead to tumor formation.
Gain of function mutations in proto-oncogenes lead to tumor formation.

P53 is a major tumor suppressor gene. Dominant negative mutations in p53 can lead to tumor formation. The dominant negative form (Ex: Truncated p53) can inhibit the function of the WT protein and result in a loss of function phenotype.

The given statement is true.