?

Cellular and Molecular Biology

Free Version

Upgrade subject to access all content

Difficult

Endomembrane System

CELLS-9M71IB

The cystic fibrosis transmembrane conductance regulator (CFTR) gene is mutated in individuals with the cystic fibrosis (CF) disease. This gene encodes the CFTR protein which is a membrane channel protein for chloride ion transport.

Most individuals with CF do not have any detectable CFTR protein in their cytoplasmic membrane despite a difference of only one amino acid at residue 508 when compared with wild-type CFTR protein.

The most likely reason for the absence of this mutant protein in the cytoplasmic membrane is

A

the protein does not get translated due to the mutation.

B

the mutant protein is too small to be transported by the endomembrane system.

C

the mutant protein has a retention tag which does not allow it to be secreted from the Golgi complex.

D

the protein fails to fold appropriately and is exported for targeted degradation.