Protein phosphorylation is commonly involved with all of the following except
A) regulation of transcription by extracellular signaling molecules.
B) enzyme activation.
C) activation of G protein-coupled receptors.
D) activation of receptor tyrosine kinases.
E) activation of protein kinase molecules.

Question

Quizplus · Accepted Answer

Protein phosphorylation is not directly involved in the activation of G protein-coupled receptors, which instead involve conformational changes induced by ligand binding. Protein phosphorylation can play a role in downstream signaling pathways activated by G protein-coupled receptors, however.

Protein Phosphorylation Is Commonly Involved with All of the Following