Ectonucleotide pyrophosphatase/phosphodiesterase family member 1 (PC-1, CD203a) is an enzyme that in humans is encoded by the ENPP1 gene. [5] [6] [7]
Ectonucleotide pyrophosphatase/phosphodiesterase family member 1 (PC-1, CD203a) is an enzyme that in humans is encoded by the ENPP1 gene. [5] [6] [7]
This gene is a member of the ecto-nucleotide pyrophosphatase/phosphodiesterase (ENPP) family. The encoded protein is a type II transmembrane glycoprotein comprising two identical disulfide-bonded subunits.
ENPP1 has broad specificity and cleaves a variety of substrates, including phosphodiester bonds of nucleotides and nucleotide sugars. ENPP1 protein may function to hydrolyze nucleoside 5′-triphosphates to their corresponding monophosphates and may also hydrolyze diadenosine polyphosphates.
The main substrate of ENNP1 is adenosine triphosphate (ATP), which is cleaved into adenosine monophosphate (AMP) and diphosphate. [8] Another notable nucleotide substrate is nicotinamide adenine dinucleotide (NAD+) which can be hydrolyzed to produce AMP. [8] ADPR can also be hydrolyzed by ENNP1 to produce AMP. [9]
Mutations in this gene have been associated with Generalized arterial calcification of infancy, ossification of the posterior longitudinal ligament of the spine (OPLL), Hypophosphatemic rickets autosomal recessive 2 (ARHR2), and insulin resistance. [6]
In a tumor microenvironment, AMP generated by ENNP1 can lead to production of adenosine, which suppresses the anti-cancer function of the immune system. [9] [10] [11]
Ectonucleotide pyrophosphatase/phosphodiesterase 1 has been shown to interact with Insulin receptor. [12]
A phosphodiesterase inhibitor is a drug that blocks one or more of the five subtypes of the enzyme phosphodiesterase (PDE), thereby preventing the inactivation of the intracellular second messengers, cyclic adenosine monophosphate (cAMP) and cyclic guanosine monophosphate (cGMP) by the respective PDE subtype(s). The ubiquitous presence of this enzyme means that non-specific inhibitors have a wide range of actions, the actions in the heart, and lungs being some of the first to find a therapeutic use.
In chemistry, pyrophosphates are phosphorus oxyanions that contain two phosphorus atoms in a P–O–P linkage. A number of pyrophosphate salts exist, such as disodium pyrophosphate (Na2H2P2O7) and tetrasodium pyrophosphate (Na4P2O7), among others. Often pyrophosphates are called diphosphates. The parent pyrophosphates are derived from partial or complete neutralization of pyrophosphoric acid. The pyrophosphate bond is also sometimes referred to as a phosphoanhydride bond, a naming convention which emphasizes the loss of water that occurs when two phosphates form a new P–O–P bond, and which mirrors the nomenclature for anhydrides of carboxylic acids. Pyrophosphates are found in ATP and other nucleotide triphosphates, which are important in biochemistry. The term pyrophosphate is also the name of esters formed by the condensation of a phosphorylated biological compound with inorganic phosphate, as for dimethylallyl pyrophosphate. This bond is also referred to as a high-energy phosphate bond.
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