Below is the molecular structure of a single bovine $\beta$-arrestin subunit. Two locations are indicated. What is most likely to interact with the protein at these locations? A) "$\beta$ARK" B) "GTP-bound G _$\alpha$ " C) "dephosphorylated GPCR" D) "phosphorylated GPCR"

Question

Quizplus · Accepted Answer

The two locations indicated in the image are the "P-loop" (between the F1 and S1 domains) and the "C-loop" (between the S1 and F10 domains). The P-loop is a binding site for phosphorylated GPCRs, so option D is most likely to interact with the protein at this location. The C-loop is involved in stabilizing the interaction between the receptor and the arrestin, making it less likely to be a binding site for the other options listed.

Below Is the Molecular Structure of a Single Bovine β\betaβ -Arrestin Subunit

Below Is the Molecular Structure of a Single Bovine $\beta$ -Arrestin Subunit