Consider the signalling pathway that proceeds through three protein kinases that are sequentially activated by phosphorylation. IN one case the kinases are held in a signalling complex by a scaffolding protein; in the other, the kinases are freely diffusing (see figure attached). Discuss the properties of these two types of organization in terms of signal amplification, speed, and potential for cross-talk between signaling pathways
In terms of signal amplification i believe the signalling complex by the scaffolding protein would be more efficient since it is origanized. Also in terms of speed it is easier to move if all kinases are ordered in an organized manner.
The scaffolding protein allows for fast signal transduction because all the kinases are in close proximity, increasing the local concentration of the kinases, so factors such as diffusion rate is no longer an issue. However, by localizing these kinases in one particular location will reduce the amount of cross-talk between other pathways because ...