In: Biology
Mutations in certain genes can interfere with DNA replication and DNA repair and lead to tumor formation (cancer). In 1-2 complete sentences, describe which cell cycle checkpoints are most likely disrupted by these genes and explain why this would lead to cancerous cells?
Answer:
During cell cycle, cell division is the main function of the cell and hence during DNA replication and cell division there are check points in the cell cycle to ensure the cycle is going in the right direction and daughter cells receive the complete copy of genome. These checkpoints avoid transmission of altered genome to daughter cells. On detection of an altered genome these check point pathways arrest sell division, carry out DNA repair if possible or signal for apoptosis. Caner cells are often defective in these check points.
Among the several checkpoints, the three main checkpoints are
In cancer cells due to mutations in the genome the very first check point that is G1 checkpoint is altered. As this is the initial check point which decides if cell must divide further or not. But due to mutation, the cancer cells do not realize this check point and cell divided uncontrollably.