Proteins acted upon by signal peptidase

Question

Quizplus · Accepted Answer

Proteins that are acted upon by signal peptidase are typically those that are being prepared for secretion or for residence in various compartments of the endomembrane system, such as the ER, Golgi apparatus, lysosomes, or the plasma membrane. After cleavage by signal peptidase, these proteins are indeed destined for further processing within the ER lumen (A) and subsequently travel within vesicles to the cis-Golgi for further sorting and modification (B). The KDEL sequence is a retention signal for proteins that are meant to stay within the ER and is not directly related to the action of signal peptidase, making C incorrect in this context.

Proteins Acted Upon by Signal Peptidase