A common core RNP structure shared between the small nucleoar box C/D RNPs and the spliceosomal U4 snRNP

Nicholas J Watkins (1) , Véronique Senty-Ségault (2, 3) , Bruno Charpentier (2, 3, 4) , Stéphanie Nottrott (1) , Patricia Fabrizio (1) , Angela Bachi (5) , Matthias Wilm (5) , Michael Rosbash (6, 4) , Christiane Branlant (2, 3) , Reinhard Lührmann (1)

1 Max-Planck-Institut für Biophysikalische Chemie - Max Planck Institute for Biophysical Chemistry [Göttingen]
2 UL - Université de Lorraine
3 AREMS - ARN-RNP, structure-fonction-maturation
4 HHMI - Howard Hughes Medical Institute
5 EMBL - European Molecular Biology Laboratory [Heidelberg]
6 Brandeis University

The box C/D snoRNAs function in directing 2'-O-methylation and/or as chaperones in the processing of ribosomal RNA. We show here that Snu13p (15.5 kD in human), a component of the U4/U6.U5 tri-snRNP, is also associated with the box C/D snoRNAs. Indeed, genetic depletion of Snu13p in yeast leads to a major defect in RNA metabolism. The box C/D motif can be folded into a stem-internal loop-stem structure, almost identical to the 15.5 kD binding site in the U4 snRNA. Consistent with this, the box C/D motif binds Snu13p/ 15.5 kD in vitro. The similarities in structure and function observed between the U4 snRNP (chaperone for U6) and the box C/D snoRNPs raises the interesting possibility that these particles may have evolved from a common ancestral RNP.

Domaines: Biochimie, Biologie Moléculaire

Nicholas J Watkins, Véronique Senty-Ségault, Bruno Charpentier, Stéphanie Nottrott, Patricia Fabrizio, et al.. A common core RNP structure shared between the small nucleoar box C/D RNPs and the spliceosomal U4 snRNP. Cell, 2000, 103 (3), pp.457-66. ⟨10.1016/S0092-8674(00)00137-9⟩. ⟨hal-01704615⟩