Alternative titles; symbols
HGNC Approved Gene Symbol: RTCA
Cytogenetic location: 1p21.2 Genomic coordinates (GRCh38) : 1:100,266,216-100,292,769 (from NCBI)
RNA 3-prime-terminal phosphate cyclase (RPC; EC 6.5.1.4) catalyzes the ATP-dependent conversion of a 3-prime phosphate to a 2-prime,3-prime-cyclic phosphodiester at the end of RNA (Genschik et al., 1997).
Genschik et al. (1997) purified RPC from HeLa cells and obtained a full-length RPC clone by PCR and screening a HeLa cell cDNA library. The deduced 366-amino acid protein has a calculated molecular mass of 39.4 kD. Northern blot analysis detected ubiquitous expression of 1.8- and 3.0-kb transcripts in human tissues and cell lines, although the ratio between the transcripts varied among tissues. Highest expression was in skeletal muscle. Immunofluorescence analysis localized epitope-tagged RPC primarily to the nucleus in HeLa cells and other mammalian cell lines. RPC is conserved among eukaryotes, bacteria, and archaea.
Genschik et al. (1997) expressed recombinant human RPC in E. coli and found that it underwent adenylation in the presence of radiolabeled ATP and catalyzed cyclization of the 3-prime-terminal phosphate in different RNA substrates. Comparison of RNA and DNA substrates with identical sequences showed that the latter were 500-fold poorer substrates for RPC. Genschik et al. (1997) stated that ATP is the best cofactor for this reaction, but GTP, CTP, and UTP, but not dATP, can also act as cofactors, although less efficiently.
Genschik et al. (1997) determined that the upstream region of the RTCD1 gene is associated with a CpG island.
The International Radiation Hybrid Mapping Consortium mapped the RTCD1 gene to chromosome 1 (SHGC-53265).
Genschik, P., Billy, E., Swianiewicz, M., Filipowicz, W. The human RNA 3-prime-terminal phosphate cyclase is a member of a new family of proteins conserved in Eucarya, Bacteria, and Archaea. EMBO J. 16: 2955-2967, 1997. [PubMed: 9184239] [Full Text: https://doi.org/10.1093/emboj/16.10.2955]