NCBI Summary:
There are at least four distinct but related alkaline phosphatases: intestinal, placental, placental-like, and liver/bone/kidney (tissue non-specific). The first three are located together on chromosome 2, while the tissue non-specific form is located on chromosome 1. The product of this gene is a membrane bound glycosylated enzyme that is not expressed in any particular tissue and is, therefore, referred to as the tissue-nonspecific form of the enzyme. The exact physiological function of the alkaline phosphatases is not known. A proposed function of this form of the enzyme is matrix mineralization; however, mice that lack a functional form of this enzyme show normal skeletal development. This enzyme has been linked directly to hypophosphatasia, a disorder that is characterized by hypercalcemia and includes skeletal defects. The character of this disorder can vary, however, depending on the specific mutation since this determines age of onset and severity of symptoms. Alternatively spliced transcript variants, which encode the same protein, have been identified for this gene. [provided by RefSeq]
General function
Enzyme
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Cellular localization
Cytoplasmic, Plasma membrane
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Ovarian function
Germ cell development
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Purification of primordial germ cells from TNAPbeta-geo mouse embryos using FACS-gal. Abe K et al. Tissue nonspecific alkaline phosphatase (TNAP), the product of the Akp2 locus, is expressed in mouse primordial germ cells (PGC) for an extensive period during embryogenesis. Mice with the Akp2tm1Sor mutant allele of TNAP express lacZ (beta-galactosidase; beta-gal) under control of the Akp2 locus. PGCs were purified from Akp2tm1Sor embryos using fluorescence activated cell sorting of beta-gal expressing cells (FACS-gal). Analysis of the purified cells by alkaline phosphatase staining and immunocytochemistry with anti-c-kit antibody demonstrated that highly (98%) purified PGCs can be isolated using this method. This technique will facilitate experiments that require highly purified preparations of PGCs including cell culture and gene expression analyses.
Expression regulated by
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Ovarian localization
Primordial Germ Cell
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TNAp is a marker for primordial germ cells.
Genesis. 2000 Feb;26(2):116-7.
Targeted insertion of Cre recombinase into the TNAP gene: excision in primordial germ cells.
Lomel頎H, Ramos-Mej韆 V, Gertsenstein M, Lobe CG, Nagy A.