Cyclic AMP can activate the synthesis of some enzymes. It is likely that the mechanism involves
A) binding of free cAMP to a nucleotide sequence in the promoter region of the gene for the enzyme.
B) phosphorylation of an acidic protein which is bound to the gene for the enzyme.
C) phosphorylation of a glucocorticoid receptor protein which then migrates to the nucleus and activates the gene for the enzyme.
D) binding of cAMP to a protein kinase regulatory subunit which migrates to the nucleus, binds to chromatin, and activates the gene for the protein.
E) phosphorylation of initiation factor IF-2 which stimulates translation of the mRNA for the enzymes.

Question

Quizplus · Accepted Answer

Binding of cAMP to a protein kinase regulatory subunit activates the catalytic subunit of the protein kinase. This complex can then migrate to the nucleus where the catalytic subunit phosphorylates transcription factors, which then bind to chromatin and activate the genes for the enzymes.

Cyclic AMP Can Activate the Synthesis of Some Enzymes