snoRNPs

Abstract

snoRNPs are nucleolus‐localized ribonucleoprotein particles that comprise small RNAs (snoRNAs) and a few associated proteins. Known snoRNPs can be subdivided into two major classes, C/D and H/ACA, which direct site‐specific 2′‐O‐ribose methylation and pseudouridylation of ribosomal RNA (rRNA) respectively. Some snoRNPs participate in precursor rRNA processing.

Keywords: snoRNAs; RNA modification; rRNA processing; methylation; pseudouridylation

Figure 1.

Structure of guide snoRNAs and their interaction with target RNAs. The secondary structures of the C/D‐box and H/ACA‐box snoRNAs are shown, with the conserved sequence elements and base‐paired target RNAs indicated. Most snoRNAs contain one rather than two functional domains. 2′‐O‐ribose methylation is carried out on the RNA residue that is base‐paired with the fifth position upstream from box D (or D′). Pseudouridine (ψ) formation in RNA occurs on the unpaired uridine residue upstream from the H box or the ACA box (usually 14–16 nt from the box). snoRNAs of each class are associated with a set of specific proteins that are not shown.

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References

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Further Reading

Eddy SR (2001) Non‐coding RNA genes and the modern RNA world. Nature Reviews Genetics 2: 919–929.

Kiss T (2001) Small nucleolar RNA‐guided post‐transcriptional modification of cellular RNAs. EMBO Journal 20: 3617–3622.

Lafontaine DL and Tollervey D (1998) Birth of the snoRNPs: the evolution of the modification‐guide snoRNAs. Trends in Biochemical Sciences 23: 383–388.

Web Links

Dyskeratosis congenita 1 (DKC1); LocusID: 1736. LocusLink: http://www.ncbi.nlm.nih.gov/LocusLink/LocRpt.cgi?l=1736

Dyskeratosis congenita 1 (DKC1); MIM number: 300126. OMIM: http://www.ncbi.nlm.nih.gov/htbin‐post/Omim/dispmim?300126

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How to Cite close
Pogačić, Vanda, and Filipowicz, Witold(Sep 2005) snoRNPs. In: eLS. John Wiley & Sons Ltd, Chichester. http://www.els.net [doi: 10.1038/npg.els.0005031]