Unit 4: Topic 4 - Changes in Signal Transduction Pathways

Question 1

Example of Signal Transduction Pathway

Answer 1

The EGF would be unable to bond, and there would be no activation of the EGF receptor. Raf would not get activated, and the phosphorylation cascade would never happen. The cell would not increase the transcription of genes and other cytosolic factors which promote cell growth and division. In summary, the effect of the mutation would be that there would be no increased transcription of genes in response to EGF.

Question 2

Example of Signal Transduction Pathway 3

Answer 2

If a phosphate group could not be removed from ERK, the phosphorylation of c-MYC, cytosolic targets, and other transcription factors wouldn’t happen. This means there would be no growth and cell division increase in response to EGF.