Question

What mediates the interaction between integral membrane proteins to be transported in COPII-coated vesicles and the COPII-coat?

1) ER export signals in the luminal tails of integral ER membrane proteins
2) ER export signals in the cytosolic tails of integral ER membrane proteins
3) ER export signals in ER phospholipids that interact with the membrane proteins
4) ER export signals in carbohydrates on the cytosolic tails of integral ER membrane proteins
5) ER export signals in carbohydrates on the luminal tails of integral ER membrane proteins

Answer 1

The interaction between integral membrane proteins and the COPII coded vesicles is medicated by specific signal, sequences and coat proteins

Answer 2

ER export signals in the cytosolic tails of integral ER membrane proteins mediate their interaction with COPII-coated vesicles for transport from the ER to the Golgi apparatus.

Step-by-step explanation:

The interaction between integral membrane proteins to be transported in COPII-coated vesicles and the COPII-coat is mediated by ER export signals in the cytosolic tails of integral ER membrane proteins. Thus, the correct answer to the question is option 2: ER export signals in the cytosolic tails of integral ER membrane proteins. Such signals are recognized by the COPII proteins, which facilitate the packaging of these integral membrane proteins into the vesicles that will transport them from the endoplasmic reticulum (ER) to the Golgi apparatus. During transit to the Golgi, the integral membrane proteins may undergo modifications, such as glycosylation, before they are sorted to their final destinations. The entire process is crucial for the correct targeting and function of membrane proteins within the cell.