Which statement correctly describes how protein kinase A can activate genes?

Question

Quizplus · Accepted Answer

Protein kinase A (PKA) is activated by cyclic AMP (cAMP) binding, which releases the catalytic subunits from the regulatory subunits. The released catalytic subunits can then enter the nucleus and phosphorylate transcription factors, such as cAMP-responsive element-binding protein (CREB), which can activate gene expression. However, PKA itself does not directly phosphorylate general transcription factors. Therefore, option A is incorrect. Furthermore, PKA is not located in the nucleus under basal conditions, so option C is also incorrect. Option D is partially correct, as nuclear PKA can phosphorylate CREB, but it does not phosphorylate general transcription factors. Therefore, the most accurate option is B, which describes how cytosolic PKA can activate genes via phosphorylation of CREB after release of the catalytic subunits in response to cAMP.

Which Statement Correctly Describes How Protein Kinase a Can Activate