title: Stanniocalcin 2: characterization of the protein and its localization to human pancreatic alpha cells.
abstract: Stanniocalcin (STC) is a hormone that was originally identified in fish, where it inhibits calcium uptake by the gills and gut and stimulates phosphate adsorption by the kidney. Recently, two mammalian homologues of stanniocalcin were identified. The first (STC1) shows 61% identity to the fish stanniocalcins and appears to have a function similar to that of the fish stanniocalcins. The second homologue (STC2) is 30-38% identical to the fish stanniocalcins, and is characterized by unique cysteine and histidine motifs that are not found in the other stanniocalcins. We purified both the native hamster and recombinant human STC2 proteins and obtained a partial amino acid sequence of the hamster protein. Both proteins behave as a disulfide bonded homodimer, which undergoes post-translational modification(s). The STC2 gene was localized to human chromosome 5q35. Northern blot analysis revealed that the primary site of human STC2 production is the pancreas, and immunostaining localized the STC2 protein to a subpopulation of cells in the islet. Double immunostaining for STC2 and either insulin or glucagon revealed that STC2 protein is found in the alpha cells, but not the beta cells. We speculate that STC2 may play a role in glucose homeostasis.
authors.affiliation: ZymoGenetics, Inc., Seattle, WA, USA. mooreb@zgi.com
authors.forename: E E
authors.initials: EE
authors.lastname: Moore
authors.forename: R E
authors.initials: RE
authors.lastname: Kuestner
authors.forename: D C
authors.initials: DC
authors.lastname: Conklin
authors.forename: T E
authors.initials: TE
authors.lastname: Whitmore
authors.forename: W
authors.initials: W
authors.lastname: Downey
authors.forename: M M
authors.initials: MM
authors.lastname: Buddle
authors.forename: R L
authors.initials: RL
authors.lastname: Adams
authors.forename: L A
authors.initials: LA
authors.lastname: Bell
authors.forename: D L
authors.initials: DL
authors.lastname: Thompson
authors.forename: A
authors.initials: A
authors.lastname: Wolf
authors.forename: L
authors.initials: L
authors.lastname: Chen
authors.forename: M R
authors.initials: MR
authors.lastname: Stamm
authors.forename: F J
authors.initials: FJ
authors.lastname: Grant
authors.forename: S
authors.initials: S
authors.lastname: Lok
authors.forename: H
authors.initials: H
authors.lastname: Ren
authors.forename: K S
authors.initials: KS
authors.lastname: De Jongh
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D015152:Blotting, Northern; D016466:CHO Cells; D002874:Chromosome Mapping; D006224:Cricetinae; D006023:Glycoproteins / Q000032:analysis* / Q000737:chemistry / Q000276:immunology; D006801:Humans; D007150:Immunohistochemistry; D036341:Intercellular Signaling Peptides and Proteins; D008969:Molecular Sequence Data; D010179:Pancreas / Q000737:chemistry*; D011994:Recombinant Proteins / Q000276:immunology
chemical_list: D006023:Glycoproteins; D036341:Intercellular Signaling Peptides and Proteins; D011994:Recombinant Proteins; C114997:STC2 protein, human