Question

QUESTION 14 You are studying a mutant cell that lacks the guanine exchange factor, SoS. What abnormalities would you expect to find in the way in which the cell responds to extracellular signal. Your complete answer should mention all the proteins interacting in some manner with SoS. TEE - T T T Arial 3 (12pt)

Answer 1

14) Son of Sevenless (SoS) are certain genes encoding guanine nucleotide exchange factors (GEF) which interact with the Ras subfamily (Small GTPases). The GEFs are proteins that activate small GTPases implicated on several signaling pathways with downstream targets. These GTPases (such as Ras) are involved in cell differentiation, proliferation, cytoskeletal organization and vesicle trafficking. If a mutation causes a lack on SoS, it would probably affect the expression of guanine nucleotide exchange factors. This could lead to a poor cellular proliferation ending in cell death. SoS has been target for numerous research about cancer where the lacking of this gene could control the excessive proliferation of tumor cells.