Final answer:
The protein p53 is encoded by a tumor suppressor gene, not a proto-oncogene, and functions to control cell growth and induce apoptosis. Proteins like Beta-Catenin, Ras, EGF receptor, and Myc are examples of those encoded by proto-oncogenes and are associated with cancer development when altered.
Step-by-step explanation:
The protein p53 is NOT encoded by a proto-oncogene. Instead, p53 is encoded by a tumor suppressor gene. Proto-oncogenes are normal genes that, when mutated or expressed at high levels, become oncogenes that can contribute to cancer. Oncogenes promote cell division, survival, and proliferation. Tumor suppressor genes like the one encoding p53, on the other hand, help protect cells from becoming cancerous by controlling cell growth and inducing apoptosis when necessary.
When Human papillomavirus (HPV) infects cells, it produces the E6 protein, which binds to p53 and marks it for degradation. This deactivation of p53 by E6 contributes to the unregulated cell division seen in cervical cancer. In contrast, proteins like Beta-Catenin, Ras, EGF receptor, and Myc are encoded by proto-oncogenes and, when altered, play a role in the development of various cancers through pathways like MAP-kinase cascade and FAS-RAS signaling associated with cell division and cellular metabolism.