Question

Which of the following is a function of SRP?

A. Pausing translation of polypeptides with an ER signal sequence

B. Binding to an SRP receptor in the ER membrane

C. Docking the ribosome over a channel

D. All of the above

Answer 1

The functions of the Signal Recognition Particle include pausing translation, binding to the SRP receptor, and docking the ribosome over an ER channel, so the correct answer is D. All of the above.

Step-by-step explanation:

The function of the Signal Recognition Particle (SRP) encompasses several essential roles during the process of protein synthesis for proteins destined for the endoplasmic reticulum (ER). Firstly, the SRP pauses translation of polypeptides that contain an ER signal sequence, which serves as a tag to direct the ribosome to the ER membrane. Secondly, the SRP is responsible for binding to an SRP receptor located in the ER membrane itself. Thirdly, after successful binding to the receptor, the SRP helps in docking the ribosome over an ER channel that allows the nascent polypeptide to be co-translationally translocated into the ER. Therefore, the correct answer to which function is performed by SRP is D. All of the above.