Alternative titles; symbols
HGNC Approved Gene Symbol: STC2
Cytogenetic location: 5q35.2 Genomic coordinates (GRCh38) : 5:173,314,723-173,328,414 (from NCBI)
By searching EST databases for sequences related to stanniocalcin-1 (STC1; 601185), Chang and Reddel (1998), DiMattia et al. (1998), and Ishibashi et al. (1998) identified human cDNAs encoding a protein that DiMattia et al. (1998) referred to as 'STC-related protein' (STCrP) and that the other authors called STC2. Ishibashi et al. (1998) reported that the predicted 302-amino acid STC2 protein shares 34% identity with STC1 and eel STC. Sequence analysis indicated that the N terminus of STC2 contains a signal peptide followed by a cysteine-rich region that may mediate homodimerization. The culture medium of mammalian cells expressing STC2 inhibited promoter activity of the sodium-phosphate cotransporter (NaPi-3; 182309) and also inhibited phosphate uptake by a kidney cell line. Ishibashi et al. (1998) stated that the function of STC2 on phosphate transport in kidney appears to be opposite to that of STC1. Northern blot analysis revealed that STC2 is expressed as multiple transcripts in several human tissues, with the strongest expression in skeletal muscle and heart. Chang and Reddel (1998) identified cDNAs encoding mouse Stc2. The predicted human and mouse STC2 proteins are approximately 88% identical.
By Western blot analysis, Jellinek et al. (2000) showed that STC1 is a secreted 31-kD doublet protein and STC2 is a secreted 32-kD protein. Autoradiographic analysis determined that STC2 is not stored or phosphorylated intracellularly and that it undergoes constitutive secretion. Exogenous STC2 is phosphorylated by an ecto-protein casein kinase-2 strictly on serine residues and can inhibit phosphorylation of cell-surface proteins. MALDI-TOF mass spectrometry indicated that STC2 is most likely phosphorylated on serine 288 in the C terminus. Jellinek et al. (2000) suggested that phosphorylation of STCs may be an important means of regulating their activity in calcium and phosphate homeostasis.
Ishibashi et al. (1998) reported that the STC2 gene contains 4 exons and that the exon-intron boundaries are completely conserved between STC2 and STC1.
Chang, A. C.-M., Reddel, R. R. Identification of a second stanniocalcin cDNA in mouse and human: stanniocalcin 2. Molec. Cell. Endocr. 141: 95-99, 1998. [PubMed: 9723890] [Full Text: https://doi.org/10.1016/s0303-7207(98)00097-5]
DiMattia, G. E., Varghese, R., Wagner, G. F. Molecular cloning and characterization of stanniocalcin-related protein. Molec. Cell. Endocr. 146: 137-140, 1998. [PubMed: 10022771] [Full Text: https://doi.org/10.1016/s0303-7207(98)00163-4]
Ishibashi, K., Miyamoto, K., Taketani, Y., Morita, K., Takeda, E., Sasaki, S., Imai, M. Molecular cloning of a second human stanniocalcin homologue (STC2). Biochem. Biophys. Res. Commun. 250: 252-258, 1998. [PubMed: 9753616] [Full Text: https://doi.org/10.1006/bbrc.1998.9300]
Jellinek, D. A., Chang, A. C., Larsen, M. R., Wang, X., Robinson, P. J., Reddel, R. R. Stanniocalcin 1 and 2 are secreted as phosphoproteins from human fibrosarcoma cells. Biochem. J. 350: 453-461, 2000. [PubMed: 10947959]