Alternative titles; symbols
HGNC Approved Gene Symbol: SNAPC1
Cytogenetic location: 14q23.2 Genomic coordinates (GRCh38): 14:61,762,420-61,796,428 (from NCBI)
A significant portion of RNA polymerase II and III transcriptional initiation events is directed by snRNA-type promoters. RNA polymerase II and III human snRNA promoters contain a similar proximal sequence element (PSE), which is involved in directing transcription by both RNA polymerases. RNA polymerase III transcription is specified by the presence, and RNA polymerase II transcription by the absence, of an adjacent TATA box. The PSE and TATA box are the only known core elements involved in both RNA polymerase II and III transcription. The snRNA-activating protein complex (SNAPC) is a basal transcription factor that binds specifically to the PSE and directs both RNA polymerase II and III snRNA gene transcription (summary by Henry et al., 1998). SNAPC consists of 5 subunits: SNPAC1, SNAPC2 (605076), SNAPC3 (602348), SNAPC4 (602777), and SNAPC5 (605979).
The TATA box-binding protein (TBP; 600075) is complexed with different sets of TBP-associated factors (TAFs; e.g., 600475) that are required for transcription. In general, each of these TBP-TAF complexes is dedicated to transcription by a single RNA polymerase. Henry et al. (1995) characterized a TBP-TAF complex called SNAPc (snRNA-activating protein complex), which is required for transcription of both RNA polymerase II and III small-nuclear RNA genes. Henry et al. (1995) purified the SNAP43 protein (SNAPC1) from HeLa cell extracts and determined partial amino acid sequence. Degenerate PCR primers were then used to identify an RNA transcript, which in turn was used to screen a human teratocarcinoma NTera2D1 cDNA library. A cDNA encoding a 368-amino acid predicted protein was identified.
Gross (2014) mapped the SNAPC1 gene to chromosome 14q23.2 based on an alignment of the SNAPC1 sequence (GenBank BC014984) with the genomic sequence (GRCh37).
Using a zebrafish genetic screen, Berg et al. (2016) identified a mutation in Snapc1b that resulted in hypersusceptibility to Mycobacterium marinum (see 607948). RNA sequencing analysis of Snapc1b mutants showed reduced expression of cathepsins B (CTSB; 116810) and L (CTSL; 116880). Mutant macrophages accumulated undigested lysosomal material, disrupting endocytic recycling and impairing macrophage migration to and engulfment of dying cells and cell debris. Macrophages with lysosomal storage could not migrate toward mycobacteria-infected macrophages undergoing apoptosis in a tuberculous granuloma. Unengulfed apoptotic macrophages underwent secondary necrosis, resulting in granuloma breakdown and increased mycobacterial growth.
Berg, R. D., Levitte, S., O'Sullivan, M. P., O'Leary, S. M., Cambier, C. J., Cameron, J., Takaki, K. K., Moens, C. B., Tobin, D. M., Keane, J., Ramakrishnan, L. Lysosomal disorders drive susceptibility to tuberculosis by compromising macrophage migration. Cell 165: 139-152, 2016. [PubMed: 27015311] [Full Text: https://doi.org/10.1016/j.cell.2016.02.034]
Gross, M. B. Personal Communication. Baltimore, Md. 4/16/2014.
Henry, R. W., Mittal, V., Ma, B., Kobayashi, R., Hernandez, N. SNAP19 mediates the assembly of a functional core promoter complex (SNAPc) shared by RNA polymerases II and III. Genes Dev. 12: 2664-2672, 1998. [PubMed: 9732265] [Full Text: https://doi.org/10.1101/gad.12.17.2664]
Henry, R. W., Sadowski, C. L., Kobayashi, R., Hernandez, N. A TBP-TAF complex required for transcription of human snRNA genes by RNA polymerases II and III. Nature 374: 653-656, 1995. [PubMed: 7715707] [Full Text: https://doi.org/10.1038/374653a0]