During the phosphoinositide cascade, phospholipase C-β cleaves PIP2 into IP3 and DAG. IP3 binds to ligand-gated calcium channels on the endoplasmic reticulum. Which protein kinase is activated by the DAG that remains in the membrane?
- A Protein kinase C ✓
- B Protein kinase A
- C Protein kinase G
- D Calmodulin-dependent kinase II
Correct answer: A. Protein kinase C
Explanation
DAG remains embedded in the plasma membrane and, in the presence of calcium released by IP3, activates protein kinase C (PKC). PKC phosphorylates numerous substrates and mediates many growth and secretory responses. PKA is activated by cAMP, PKG by cGMP, and CaMKII by calmodulin-bound calcium, not by DAG.
Reference: Robbins and Cotran Pathologic Basis of Disease, 10th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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