Oncogenes

This version of the course is no longer available.
Need multiple seats for your university or lab? Get a quote
The page below is a sample from the LabCE course . Access the complete course and earn ASCLS P.A.C.E.-approved continuing education credits by subscribing online.

Learn more about (online CE course)
Oncogenes

Continuing the analogy of a brakes and gas pedals in a car, the proto-oncogenes in the cell are akin to the gas pedal. They signal the cell when conditions are favorable for growth. If the gas pedal gets stuck, the car may continue to go even if the brake is applied. This is also true for proto-oncogenes. In order for a proto-oncogene to become an oncogene, it needs to have had a DNA mutation causing the oncoprotein to gain a function that would normally only turn on when signaled to do so. There are only a few specific mutations that can cause a gain of function mutation in an oncogene. An oncogene with an activating mutation that gets transcribed into an oncoprotein will continuously signal for the cell to continue to replicate even when the conditions are not favorable. This can also lead to tumor formation. Common proto-oncogenes include Ras, Raf, Myc, and ERK.
Some oncogenes are formed by the relocation of their gene next another gene that promotes transcription. This relocation occurs during cellular replication and can often be visualized at the chromosome level. This can cause an over-abundance of the oncoprotein. The BCR-ABL fusion is a well-known example of this type oncogene.
Image courtesy of Wikimedia

Oncogenes act as the gas pedal for cellular replication