Some theoretical questions of the peptide and steroid hormone regulation. Part II.: The second messenger system.
The "second messenger system" has been analysed regarding its possibilities for containing and transferring highly specific molecular, biological information. Very heterogeneous molecules were found behind the different - cyclase, diesterase, kinase,... -  activities of the system, whereas the connection realized between them by cyclic nucleotides was very poor. So, I constructed a theoretical model mostly on the basis of real and known experimental facts to resolve this obvious contradiction and make the second messenger system adequate as a highly specific biological informational channel.
D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases / Q000502:physiology*; D000262:Adenylyl Cyclases / Q000502:physiology*; D000818:Animals; D001665:Binding Sites; D006162:Guanylate Cyclase / Q000502:physiology*; D006728:Hormones / Q000494:pharmacology*; D006801:Humans; D008954:Models, Biological; D009711:Nucleotides / Q000378:metabolism; D010727:Phosphoric Diester Hydrolases / Q000502:physiology*; D010766:Phosphorylation; D011494:Protein Kinases / Q000502:physiology*
D006728:Hormones; D009711:Nucleotides; D011494:Protein Kinases; D015087:2',3'-Cyclic-Nucleotide Phosphodiesterases; D010727:Phosphoric Diester Hydrolases; D000262:Adenylyl Cyclases; D006162:Guanylate Cyclase