Question

Is important for retrograde traffic from the Golgi complex back to the ER.

A) Clathrin-coated
B) COPI-coated
C) COPII-coated
D) COPI/COPII-coated
E) All
F) None

Answer 1

COPI-coated vesicles facilitate retrograde traffic from the Golgi complex back to the ER, returning proteins and lipids needed for cellular function.

Step-by-step explanation:

The retrograde traffic from the Golgi complex back to the ER is crucial for maintaining cellular function by recycling certain proteins and lipids. The type of vesicle coat protein involved in retrograde transport is the COPI-coated vesicle. The COPI-coated vesicles are responsible for the reverse transport, taking proteins that have been mis-sorted or need to function back in the ER from the Golgi apparatus. These proteins include enzymes necessary for the early stages of protein processing and certain growth regulators. By contrast, COPII-coated vesicles are generally involved in anterograde transport, moving materials from the ER to the Golgi complex.