U6 spliceosomal RNA

U6 spliceosomal RNA
Identifiers
SymbolU6
RfamRF00026
Other data
RNA typeGene; snRNA; splicing
Domain(s)Eukaryota
GOGO:0000351 GO:0000353 GO:0030621 GO:0005688 GO:0046540
SOSO:0000396
PDB structuresPDBe

U6 snRNA is the non-coding small nuclear RNA (snRNA) component of U6 snRNP (small nuclear ribonucleoprotein), an RNA-protein complex that combines with other snRNPs, unmodified pre-mRNA, and various other proteins to assemble a spliceosome, a large RNA-protein molecular complex that catalyzes the excision of introns from pre-mRNA. Splicing, or the removal of introns, is a major aspect of post-transcriptional modification and takes place only in the nucleus of eukaryotes.

The RNA sequence of U6 is the most highly conserved across species of all five of the snRNAs involved in the spliceosome,[1] suggesting that the function of the U6 snRNA has remained both crucial and unchanged through evolution.

It is common in vertebrate genomes to find many copies of the U6 snRNA gene or U6-derived pseudogenes.[2] This prevalence of "back-ups" of the U6 snRNA gene in vertebrates further implies its evolutionary importance to organism viability.

The U6 snRNA gene has been isolated in many organisms,[3] including C. elegans.[4] Among them, baker's yeast (Saccharomyces cerevisiae) is a commonly used model organism in the study of snRNAs.

The structure and catalytic mechanism of U6 snRNA resembles that of domain V of group II introns.[5][6] The formation of the triple helix in U6 snRNA is deemed to be important in splicing activity, where its role is to bring the catalytic site to the splice site.[6]

  1. ^ Brow DA, Guthrie C (July 1988). "Spliceosomal RNA U6 is remarkably conserved from yeast to mammals". Nature. 334 (6179): 213–8. Bibcode:1988Natur.334..213B. doi:10.1038/334213a0. PMID 3041282. S2CID 4236176.
  2. ^ Marz M, Kirsten T, Stadler PF (December 2008). "Evolution of spliceosomal snRNA genes in metazoan animals". Journal of Molecular Evolution (Submitted manuscript). 67 (6): 594–607. Bibcode:2008JMolE..67..594M. doi:10.1007/s00239-008-9149-6. PMID 19030770. S2CID 18830327.
  3. ^ Anderson MA, Purcell J, Verkuijl SA, Norman VC, Leftwich PT, Harvey-Samuel T, Alphey LS (March 2020). "In Vitro Validation of Pol III Promoters". ACS Synthetic Biology. 9 (3): 678–681. doi:10.1021/acssynbio.9b00436. PMC 7093051. PMID 32129976.
  4. ^ Thomas J, Lea K, Zucker-Aprison E, Blumenthal T (May 1990). "The spliceosomal snRNAs of Caenorhabditis elegans". Nucleic Acids Research. 18 (9): 2633–42. doi:10.1093/nar/18.9.2633. PMC 330746. PMID 2339054.
  5. ^ Toor N, Keating KS, Taylor SD, Pyle AM (April 2008). "Crystal structure of a self-spliced group II intron". Science. 320 (5872): 77–82. Bibcode:2008Sci...320...77T. doi:10.1126/science.1153803. PMC 4406475. PMID 18388288.
  6. ^ a b Fica SM, Mefford MA, Piccirilli JA, Staley JP (May 2014). "Evidence for a group II intron-like catalytic triplex in the spliceosome". Nature Structural & Molecular Biology. 21 (5): 464–471. doi:10.1038/nsmb.2815. PMC 4257784. PMID 24747940.