A researcher is using a small molecule as an inhibitor to manipulate a signaling pathway. This inhibitor prevents phosphorylation and MOST likely targets a:
A)G protein-coupled receptor.
B)G protein.
C)receptor kinase.
D)ligand-gated ion channel.
E)phosphatase.

Question

Quizplus · Accepted Answer

The inhibitor prevents phosphorylation, which is the addition of a phosphate group catalyzed by a kinase enzyme. Therefore, the most likely target of the inhibitor is a receptor kinase, which adds the phosphate group to a signaling molecule.

A Researcher Is Using a Small Molecule as an Inhibitor