The sequence Lys-Asp-Glu-Leu (KDEL) serves as an ER retention signal for proteins by binding to KDEL receptors that
A) hold the proteins in the rough ER.
B) hold the proteins in the smooth ER.
C) hold the proteins in both the smooth ER and rough ER and prevent their transport to the Golgi apparatus.
D) transport the proteins from the Golgi apparatus back to the ER.

Question

Quizplus · Accepted Answer

The KDEL sequence binds to KDEL receptors that transport the proteins from the Golgi apparatus back to the ER. Therefore, choice D is the best choice as it accurately describes the role of KDEL receptors in protein transport. The other choices are incorrect as they do not reflect the known function of KDEL signals and receptors in protein trafficking.

The Sequence Lys-Asp-Glu-Leu (KDEL) Serves as an ER Retention Signal