Plasma membrane proteins contain a signal sequence and
A) a stop-transfer peptide sequence.
B) mannose-6-phosphate.
C) a nuclear localization signal.
D) a docking protein sequence.
E) a KDEL sequence.

Question

Quizplus · Accepted Answer

A signal sequence is necessary to direct proteins to the plasma membrane, and a stop-transfer peptide sequence is needed to anchor the protein in the membrane. Mannose-6-phosphate is a carbohydrate modification found in lysosomal enzymes, not plasma membrane proteins. Nuclear localization signals and docking protein sequences are not relevant to plasma membrane proteins. The KDEL sequence is a motif found in ER resident proteins that directs them back to the ER if mistakenly trafficked to the Golgi or plasma membrane.

Plasma Membrane Proteins Contain a Signal Sequence and