In polarized epithelial cells, membrane proteins containing a dileucine (LL) motif in their cytoplasmic domain are
A) retained in the Golgi apparatus.
B) targeted to lysosomes.
C) targeted to the basolateral plasma membrane.
D) targeted to the apical plasma membrane.

Question

Quizplus · Accepted Answer

The dileucine (LL) motif in the cytoplasmic domain of membrane proteins is a signal for targeting to the basolateral plasma membrane in polarized epithelial cells. This motif is recognized by adaptins in the trans-Golgi network, which then direct the proteins to the basolateral surface.

In Polarized Epithelial Cells, Membrane Proteins Containing a Dileucine (LL)