Question

1. A poi̾nt mutation in the EFG tyrosi̾ne kinase receptor has been shown to prevent dimeri̾zation of the receptor subuni̾ts. What effect, if any, will this have on signal transducti̾on? Explain

2.Whạt would be the effect, if ạny, on cell division normạlly ạctivạted by the EFG signạling pạthwạy if ạ cell is infected with ạ virus which encodes ạ tyrosine phosphạtạse specific for Receptor Tyrosine Kinạses? Explạin.

Answer 1

If there is a mutation in receptor dimerization then cross phosphorylation on tyrosine located on receptor won't take place so it will prevent further downstream signalling .

Normal signalling pathway - ligand bind to receptor then receptor dimerization takes place and it induced cross phosphorylation on tyrosine and this further activates downstream signalling .

2. Tyrosine phosphatase will remove phosphate group from tyrosine and this will further prevent downstream signalling , so cell division won't take place even in the presence of EGF.