Detailed Instructions: In this task you will be given a text passage from a trivia quiz. You should choose the category this question belongs to from these categories: History, Science, Social Science, Fine Arts, Literature. You can only choose one category, so if in doubt, please choose the closest match.
Problem:Bucladesine is used as an analog of this compound, and theophylline inhibits the enzyme that breaks it down. In the temporal lobe, this compound activates HNC channels, and it leads to the activation of the RAPGEF3 protein. Cholera toxin increases the levels of this compound by ribosylating G-proteins, and in the lac operon, this compound binds to the Catabolite Activator Protein, which enhances RNA polymerase binding to the promoter. Another protein that binds to it contains two catalytic and two regulatory subunits, Protein Kinase A. Usually destroyed by phosphodiesterase and created by adenylate cyclase, FTP, name this second messenger, a cyclic nucleotide often created from ATP.
Solution:
Science