MCQ-Effect of a scaffolding protein on Signaling

[TytoAlba95]

Homework Statement

NA

Relevant Equations

NA

My understanding:
A) As in RTK signalling in which Raf-MEK-ERK are bound to KSR, they are close enough and in proper orientations to transduce the signal faster than when they are not in a complex. So A is correct.
B) Correct. Because to cross-link with other signalling pathways the kinases have to dissociate first, which is not happening in this case.
C) I don't understand how being associated or not associated with a scaffolding protein might influence signal amplification.
D) This statement is the opposite of B and is correct, and in this case, the kinases are free to interact with other signalling proteins.

The correct answer is C.

 

[Ygggdrasil]

C is the correct answer.

To understand why C is not true, consider the Raf-MEK-ERK cascade. If these three kinases are scaffolded together, how many molecules of MEK will a single Raf kinase be able to activate? If these three kinases are freely diffusing, how many molecules of MEK will a single Raf kinase be able to activate?

 

[TytoAlba95]

To understand why C is not true, consider the Raf-MEK-ERK cascade. If these three kinases are scaffolded together, how many molecules of MEK will a single Raf kinase be able to activate? If these three kinases are freely diffusing, how many molecules of MEK will a single Raf kinase be able to activate?

Wow! You put it so simply. You truly are a great teacher. : )