2c1w
THE STRUCTURE OF XENDOU: A SPLICING INDEPENDENT SNORNA PROCESSING ENDORIBONUCLEASE
OverviewOverview
Small nucleolar RNAs (snoRNAs) play a key role in eukaryotic ribosome biogenesis. In most cases, snoRNAs are encoded in introns and are released through the splicing reaction. Some snoRNAs are, instead, produced by an alternative pathway consisting of endonucleolytic processing of pre-mRNA. XendoU, the endoribonuclease responsible for this activity, is a U-specific, metal-dependent enzyme that releases products with 2'-3' cyclic phosphate termini. XendoU is broadly conserved among eukaryotes, and it is a genetic marker of nidoviruses, including the severe acute respiratory syndrome coronavirus, where it is essential for replication and transcription. We have determined by crystallography the structure of XendoU that, by refined search methodologies, appears to display a unique fold. Based on sequence conservation, mutagenesis, and docking simulations, we have identified the active site. The conserved structural determinants of this site may provide a framework for attempting to design antiviral drugs to interfere with the infectious nidovirus life cycle.
About this StructureAbout this Structure
2C1W is a Single protein structure of sequence from Xenopus laevis. Full crystallographic information is available from OCA.
ReferenceReference
The structure of the endoribonuclease XendoU: From small nucleolar RNA processing to severe acute respiratory syndrome coronavirus replication., Renzi F, Caffarelli E, Laneve P, Bozzoni I, Brunori M, Vallone B, Proc Natl Acad Sci U S A. 2006 Aug 15;103(33):12365-70. Epub 2006 Aug 8. PMID:16895992 Page seeded by OCA on Sat May 3 21:07:15 2008