Alternative titles; symbols
HGNC Approved Gene Symbol: PSMG1
Cytogenetic location: 21q22.2 Genomic coordinates (GRCh38) : 21:39,174,769-39,183,514 (from NCBI)
By searching an EST database for genes between markers D21S343 and D21S268 in Down syndrome (190685) critical region 2, Vidal-Taboada et al. (1998) identified DSCR2, which they termed C21LRP (chromosome 21 leucine-rich protein). The deduced 288-amino acid DSCR2 protein contains 2 transmembrane helices. Northern blot analysis detected high expression of a 1.3-kb DSCR2 transcript in testis and in the Jurkat leukemia cell line. RT-PCR analysis detected DSCR2 mRNA in brain, colon, leukocytes, breast, and testis, as well as in all fetal tissues tested. Vidal-Taboada et al. (2000) cloned the mouse Dscr2 gene and found that it is widely expressed in adult mouse tissues and throughout all stages of mouse embryo development.
Hirano et al. (2005) reported 2 chaperones designated proteasome-assembling chaperone-1 (PAC1) and PAC2 (609702), that are involved in the maturation of the mammalian 20S proteasomes. PAC1 and PAC2 associate as heterodimers with proteasome precursors and are degraded after formation of the 20S proteasome is completed. Overexpression of PAC1 or PAC2 accelerates the formation of precursor proteasomes, whereas knockdown by short interfering RNA impairs it, resulting in poor maturation of 20S proteasomes. Furthermore, Hirano et al. (2005) showed that the PAC complex provides a scaffold for alpha ring formation and keeps the alpha rings competent for the subsequent formation of half-proteasomes. Thus, Hirano et al. (2005) concluded that their results identify a mechanism for the correct assembly of 20S proteasomes.
Vidal-Taboada et al. (1998) identified the DSCR2 gene on chromosome 21q22.3.
Hirano, Y., Hendil, K. B., Yashiroda, H., Iemura, S., Nagane, R., Hioki, Y., Natsume, T., Tanaka, K., Murata, S. A heterodimeric complex that promotes the assembly of mammalian 20S proteasomes. Nature 437: 1381-1385, 2005. [PubMed: 16251969] [Full Text: https://doi.org/10.1038/nature04106]
Vidal-Taboada, J. M., Lu, A., Pique, M., Pons, G., Gil, J., Oliva, R. Down syndrome critical region gene 2: expression during mouse development and in human cell lines indicates a function related to cell proliferation. Biochem. Biophys. Res. Commun. 272: 156-163, 2000. [PubMed: 10872820] [Full Text: https://doi.org/10.1006/bbrc.2000.2726]
Vidal-Taboada, J. M., Sanz, S., Egeo, A., Scartezzini, P., Oliva, R. Identification and characterization of a new gene from human chromosome 21 between markers D21S343 and D21S268 encoding a leucine-rich protein. Biochem. Biophys. Res. Commun. 250: 547-554, 1998. [PubMed: 9784380] [Full Text: https://doi.org/10.1006/bbrc.1998.9352]