U2 spliceosomal RNA

From Wikipedia, the free encyclopedia

U2 spliceosomal RNA

Type:	Gene; snRNA; splicing;
2° structure:	Published^[1]; Griffiths-Jones SR
Seed alignment:	The uRNA database^[2]; Griffiths-Jones SR
Avg length:	177.6 nucleotides
Avg identity:	62%

U2 spliceosomal RNA is a small nuclear RNA (snRNA) component of the spliceosome (involved in pre-mRNA splicing). Complementary binding between U2 snRNA (in an area lying towards the 5' end but 3' to hairpin I) and the branchpoint sequence (BPS) of the intron results in the bulging out of an unpaired adenosine, on the BPS, which initiates a nucleophilic attack at the intronic 5' splice site, thus starting the first of two transesterification reactions that mediate splicing.

[edit] References

^ Thomas, J; Lea K, Zucker-Aprison E, Blumenthal T (1990). "The spliceosomal snRNAs of Caenorhabditis elegans". Nucleic Acids Res 18: 2633–2642. doi:10.1093/nar/18.9.2633. PMID 2339054.
^ Zwieb, C (1997). "The uRNA database". Nucleic Acids Res 25: 102–103. doi:10.1093/nar/25.1.102. PMID 9016512.

Newby, MI; Greenbaum NL (2001). "A conserved pseudouridine modification in eukaryotic U2 snRNA induces a change in branch-site architecture". RNA 7: 833–845. doi:10.1017/S1355838201002308. PMID 11424937.
Berglund, JA; Rosbash M, Schultz SC (2001). "Crystal structure of a model branchpoint-U2 snRNA duplex containing bulged adenosines". RNA 7: 682–691. doi:10.1017/S1355838201002187. PMID 11350032.