Distinguish between oncogenes and proto-oncogenes. In what ways can proto-oncogenes be converted to oncogenes?

Verified step by step guidance

1. Define proto-oncogenes as normal genes that code for proteins involved in cell growth and division, playing a crucial role in regulating normal cellular functions.
2. Explain that oncogenes are mutated or abnormally expressed versions of proto-oncogenes that can lead to uncontrolled cell proliferation and contribute to cancer development.
3. Describe the mechanisms by which proto-oncogenes can be converted into oncogenes, including point mutations that alter the gene's function, gene amplification leading to overexpression, and chromosomal translocations that place the gene under the control of a strong promoter or create fusion proteins.
4. Illustrate how these changes result in the proto-oncogene gaining a 'gain-of-function' mutation, causing the protein product to be overactive or constitutively active, thereby promoting oncogenic transformation.
5. Summarize by emphasizing the importance of tight regulation of proto-oncogenes in normal cells and how their dysregulation through various genetic alterations leads to oncogene formation and cancer progression.

Key Concepts

Proto-oncogenes

Proto-oncogenes are normal genes that regulate cell growth and division. They encode proteins involved in signaling pathways that promote cell proliferation and survival. Under normal conditions, they help maintain healthy cell function.

Oncogenes

Oncogenes are mutated or abnormally expressed versions of proto-oncogenes that drive uncontrolled cell division, leading to cancer. They act dominantly to promote tumor formation by overriding normal regulatory mechanisms.

Conversion of Proto-oncogenes to Oncogenes

Proto-oncogenes can become oncogenes through mutations, gene amplification, or chromosomal translocations. These changes can increase gene expression or produce altered proteins that continuously activate growth signals, contributing to cancer development.