Alternative titles; symbols
HGNC Approved Gene Symbol: SNTB2
Cytogenetic location: 16q22.1 Genomic coordinates (GRCh38): 16:69,187,164-69,309,052 (from NCBI)
The syntrophin family of dystrophin (300377)-associated proteins consists of 3 isoforms, alpha-1 (601017), beta-1 (600026), and beta-2, each encoded by a distinct gene. Each syntrophin has approximately 50% amino acid identity with the other 2. The 3 syntrophins can be separated into 2 classes based on isoelectric point: the acidic isoform, alpha-1-syntrophin (pI = 6.7) and the 2 basic forms, beta-1 and beta-2 (pI = 9.0). Adams et al. (1995) cloned the mouse beta-2-syntrophin gene.
Ahn et al. (1996) found that the deduced amino acid sequences of human beta-2-syntrophin and alpha-1-syntrophin are nearly identical to their homologs in mouse, suggesting a strong functional conservation among the individual isoforms. Much like beta-1-syntrophin, human beta-2-syntrophin has multiple transcript classes and is expressed widely, although in a distinct pattern of relative abundance. In contrast, human alpha-1-syntrophin is most abundant in heart and skeletal muscle, and less so in other tissues.
Adams et al. (1995) found that the mouse Sntb2 gene is 33 kb long with 7 exons, all of which have homologs at the corresponding position in the alpha-1-syntrophin gene. Primer extension analysis revealed a single transcription initiation site in the beta-2 gene.
By analysis of interspecific backcrosses, Adams et al. (1995) mapped the mouse Sntb2 gene to chromosome 8. By Southern blot analysis of hamster/human somatic cell hybrid DNAs, they mapped the human SNTB2 gene to chromosome 16. By PCR analysis of somatic cell hybrids and fluorescence in situ hybridization, Ahn et al. (1996) localized the SNTB2 gene to 16q22-q23.
Adams, M. E., Dwyer, T. M., Dowler, L. L., White, R. A., Froehner, S. C. Mouse alpha-1- and beta-2-syntrophin gene structure, chromosome localization, and homology with a discs large domain. J. Biol. Chem. 270: 25859-25865, 1995. [PubMed: 7592771] [Full Text: https://doi.org/10.1074/jbc.270.43.25859]
Ahn, A. H., Freener, C. A., Gussoni, E., Yoshida, M., Ozawa, E., Kunkel, L. M. The three human syntrophin genes are expressed in diverse tissues, have distinct chromosomal locations, and each bind to dystrophin and its relatives. J. Biol. Chem. 271: 2724-2730, 1996. [PubMed: 8576247] [Full Text: https://doi.org/10.1074/jbc.271.5.2724]