Question

How does the active Rab protein differ in properties from the inactive Rab proteins?

A. Active Rab is phosphorylated, while inactive Rab is dephosphorylated.
B. Active Rab has bound GTP, while inactive Rab has bound GDP.
C. Active Rab is membrane-bound, while inactive Rab is cytoplasmic.
D. Active Rab is larger in size, while inactive Rab is smaller.

Answer 1

Active Rab proteins are distinguished from inactive Rab proteins by their binding of guanine nucleotides; active Rab is bound to GTP, while inactive Rab is bound to GDP.

Step-by-step explanation:

The properties that distinguish active Rab protein from inactive Rab proteins involve how they interact with guanine nucleotides. The correct answer to the question, "How does the active Rab protein differ in properties from the inactive Rab proteins?" is B. Active Rab has bound GTP, while inactive Rab has bound GDP. This is a fundamental aspect of how G-proteins operate in cell signaling pathways.