Search results
Results From The WOW.Com Content Network
Cyclic guanosine monophosphate (cGMP) is a cyclic nucleotide derived from guanosine triphosphate (GTP). cGMP acts as a second messenger much like cyclic AMP.Its most likely mechanism of action is activation of intracellular protein kinases in response to the binding of membrane-impermeable peptide hormones to the external cell surface. [1]
Guanylate cyclase (EC 4.6.1.2, also known as guanyl cyclase, guanylyl cyclase, or GC; systematic name GTP diphosphate-lyase (cyclizing; 3′,5′-cyclic-GMP-forming)) is a lyase enzyme that converts guanosine triphosphate (GTP) to cyclic guanosine monophosphate (cGMP) and pyrophosphate: [1] GTP = 3′,5′-cyclic GMP + diphosphate
In mammalian cells, cGAMP is synthesized by cyclic GMP-AMP synthase from ATP and GTP upon cytosolic DNA stimulation. [2] cGAMP produced by cGAS contains mixed phosphodiester linkages, with one between 2'-OH of GMP and 5'-phosphate of AMP and the other between 3'-OH of AMP and 5'-phosphate of GMP. [3] [4] [5] [6]
There are three basic types of secondary messenger molecules: [citation needed] Hydrophobic molecules: water-insoluble molecules such as diacylglycerol, and phosphatidylinositols, which are membrane-associated and diffuse from the plasma membrane into the intermembrane space where they can reach and regulate membrane-associated effector proteins.
The R domain contains specific allosteric cGMP binding site that controls the enzymes function. This specific binding site consists of subdomain GAF (cGMP-specific cGMP-stimulated PDE, adenylate cyclase, and FhlA) which is located in the N-terminal section of the specific proteins.
ANP activation of the ANP catalytic receptor will stimulate its intracellular guanylyl cyclase activity to convert GTP to cGMP. cGMP will then stimulate cGMP-dependent protein kinase (PKG), which will then induce smooth muscle relaxation. This is particularly important in the vasculature, where vascular smooth muscle will bind ANP released as a ...
In its Fe(II) form, this heme moiety is the target of nitric oxide, which is synthesized by endothelial cells following appropriate stimulation. Binding of nitric oxide to the heme results in activation of the C-terminal catalytic domain, which produces cGMP from GTP.
In capping enzymes, a highly conserved lysine residue serves as the catalytic residue that forms a covalent enzyme-GMP complex. [ 1 ] The transfer RNA (tRNA) for histidine is unique among eukaryotic tRNAs in requiring the addition of a guanine nucleotide before being aminoacylated by the histidine tRNA synthetase .