Question

Why is the src gene from RSV responsible for transformation of cells? (Transformation being the change from normal cell to cancerous) How did Bishop and Varmus define the transformation-associated sequences of RSV genome?

Answer 1

RSV (Rous Sarcoma Virus) is a cancer causing retrovirus.The four genes in RSV namely- gag, pol, env, src.

src gene is oncogenic ( produce growth of tumours and tumour cells) as it triggers uncontrolled growth in abnormal host cells. It was the first retroviral oncogene discovered.The src gene was taken up by RSV and incorporated into its genome benefitting it with the advantage of being able to stimulate the uncontrolled mitosis of host cellsand provides infection in abundance of cells.

Michael Bishop and Harold E Varmus investigated the Rous virus oncogene. They isolated a gene and created a probe that was complementary to it, Uing this probe they found that similar genes were present in healthy chicken cells and in the cells of many other animals, in fixed position in their genomes.The gene was found to control growth and cell division in normal cells.