title: Chromosomal localization of two human genes involved in phosphate homeostasis: the type IIb sodium-phosphate cotransporter and stanniocalcin-2.
abstract: Extracellular phosphate concentrations are maintained by coordinated regulation of specific homeostatic mechanisms. A novel gene, the type IIb sodium-phosphate cotransporter (Npt2b), was recently cloned and is expressed within intestinal tissues, indicating that the transporter may be an important regulator of phosphate reabsorption. Another gene, human stanniocalcin-2 (STC2), was previously shown to decrease phosphate uptake into kidney cells in vitro. Because of the important role that STC2 may play in phosphate homeostasis, we considered the peptide hormone a candidate for the phosphate wasting disease autosomal dominant hypophosphatemic rickets (ADHR), previously localized to chromosome 12p13. The purpose of our study was to determine the chromosomal localization of human NPT2b and STC2. In the present work, NPT2b was localized to human chromosome 4p15-p16, and STC2 to 5q33-tel. Because STC2 did not map to 12p13, the hormone was excluded as the ADHR gene, however it should be considered a candidate for other diseases involving phosphate homeostasis.
authors.affiliation: Department of Medicine, Indiana University School of Medicine, Indianapolis 46202, USA.
authors.forename: K E
authors.initials: KE
authors.lastname: White
authors.forename: J
authors.initials: J
authors.lastname: Biber
authors.forename: H
authors.initials: H
authors.lastname: Murer
authors.forename: M J
authors.initials: MJ
authors.lastname: Econs
mesh_terms: D002118:Calcium / Q000378:metabolism*; D002352:Carrier Proteins / Q000235:genetics*; D002874:Chromosome Mapping; D002894:Chromosomes, Human, Pair 4 / Q000235:genetics; D002895:Chromosomes, Human, Pair 5 / Q000235:genetics; D006023:Glycoproteins / Q000235:genetics*; D006706:Homeostasis / Q000235:genetics*; D006801:Humans; D007015:Hypophosphatemia, Familial / Q000235:genetics; D036341:Intercellular Signaling Peptides and Proteins; D007413:Intestinal Mucosa / Q000378:metabolism; D010710:Phosphates / Q000378:metabolism*; D012964:Sodium / Q000378:metabolism*; D050608:Sodium-Phosphate Cotransporter Proteins; D050614:Sodium-Phosphate Cotransporter Proteins, Type IIb; D027981:Symporters
chemical_list: D002352:Carrier Proteins; D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D010710:Phosphates; C493557:SLC34A2 protein, human; C114997:STC2 protein, human; D050608:Sodium-Phosphate Cotransporter Proteins; D050614:Sodium-Phosphate Cotransporter Proteins, Type IIb; D027981:Symporters; D012964:Sodium; D002118:Calcium