Ectonucleotide pyrophosphatase/phosphodiesterase family member 3 is an enzyme that in humans is encoded by the ENPP3gene.
Function
The protein encoded by this gene belongs to a series of ectoenzymes that are involved in hydrolysis of extracellular nucleotides. These ectoenzymes possess ATPase and ATP pyrophosphatase activities and are type II transmembrane proteins. Expression of the related rat mRNA has been found in a subset of immature glial cells and in the alimentary tract. The corresponding rat protein has been detected in the pancreas, small intestine, colon, and liver. The human mRNA is expressed in glioma cells, prostate, and uterus. Expression of the human protein has been detected in uterus, basophils, and mast cells.
This protein has also been used in conjunction with CD63 as a marker for activated basophils in the Basophil Activation Test for IgE mediated allergic reactions.
ENPP3 hydrolyzes the immunomodulatory second messenger extracellular cyclic GMP-AMP (cGAMP), a signaling molecule that activates the STING pathway. Along with its paralog ENPP1, ENPP3 helps control extracellular cGAMP levels and accounts for the cGAMP hydrolysis observed when ENPP1 is absent. By limiting the amount of extracellular cGAMP available to activate STING, ENPP3 can dampen immune signaling and function as an innate immune checkpoint.
↑"Human PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
↑"Mouse PubMed Reference:". National Center for Biotechnology Information, U.S. National Library of Medicine.
↑Jin-Hua P, Goding JW, Nakamura H, Sano K (October 1997). "Molecular cloning and chromosomal localization of PD-Ibeta (PDNP3), a new member of the human phosphodiesterase I genes". Genomics. 45 (2): 412–415. doi:10.1006/geno.1997.4949. PMID9344668.
Bühring HJ, Streble A, Valent P (April 2004). "The basophil-specific ectoenzyme E-NPP3 (CD203c) as a marker for cell activation and allergy diagnosis". International Archives of Allergy and Immunology. 133 (4): 317–329. doi:10.1159/000077351. PMID15031605. S2CID12238348.
Andoh K, Piao JH, Terashima K, Nakamura H, Sano K (September 1999). "Genomic structure and promoter analysis of the ecto-phosphodiesterase I gene (PDNP3) expressed in glial cells". Biochimica et Biophysica Acta (BBA) - Gene Structure and Expression. 1446 (3): 213–224. doi:10.1016/s0167-4781(99)00090-1. PMID10524196.
Yano Y, Hayashi Y, Sano K, Shinmaru H, Kuroda Y, Yokozaki H, etal. (November 2003). "Expression and localization of ecto-nucleotide pyrophosphatase/phosphodiesterase I-3 (E-NPP3/CD203c/PD-I beta/B10/gp130RB13-6) in human colon carcinoma". International Journal of Molecular Medicine. 12 (5): 763–766. doi:10.3892/ijmm.12.5.763. PMID14533006.
Yano Y, Hayashi Y, Sano K, Nagano H, Nakaji M, Seo Y, etal. (April 2004). "Expression and localization of ecto-nucleotide pyrophosphatase/phosphodiesterase I-1 (E-NPP1/PC-1) and -3 (E-NPP3/CD203c/PD-Ibeta/B10/gp130(RB13-6)) in inflammatory and neoplastic bile duct diseases". Cancer Letters. 207 (2): 139–147. doi:10.1016/j.canlet.2003.11.002. PMID15072822.
Elbatarny HS, Maurice DH (October 2005). "Leptin-mediated activation of human platelets: involvement of a leptin receptor and phosphodiesterase 3A-containing cellular signaling complex". American Journal of Physiology. Endocrinology and Metabolism. 289 (4): E695–702. doi:10.1152/ajpendo.00125.2005. PMID15886225.
Ocmant A, Peignois Y, Mulier S, Hanssens L, Michils A, Schandené L (March 2007). "Flow cytometry for basophil activation markers: the measurement of CD203c up-regulation is as reliable as CD63 expression in the diagnosis of cat allergy". Journal of Immunological Methods. 320 (1–2): 40–48. doi:10.1016/j.jim.2006.12.002. PMID17275019.