0 avis
Box C/D snoRNPs: solid-state NMR fingerprint of an early-stage 50 kDa assembly inermediate
Archive ouverte
Edité par CCSD -
International audience. Many cellular functions rely on stable protein-only or protein-RNA complexes. Deciphering their assembly mechanism is a key question in cell biology.We here focus on box C/D snoRNPs (Ribo Nucleo Proteins), involved in ribosome biogenesis and present in archae, yeast and humans. Despite their relatively simple composition – one snoRNA and 4 core proteins – these particles don't self-assemble and their formation requires a large number of other proteins, called assembly factors.We use solid-state NMR to get atomic-scale information on the early part of Saccharomyces cerevisiae box C/D snoRNP assembly pathway, through the study of a protein complex composed of Snu13p core protein and Rsa1p:Hit1p assembly factors.Spectra of uniformly 13C,15N labeled Snu13p co-sedimented with unlabeled Rsa1p:Hit1p show good linewidths.We present first solid-state 13C and 15N assignments of the 126-residue protein Snu13p in the context of the 50 kDa complex. They are compared with solution chemical shifts of both the isolated protein and the protein in the presence of a 22-residue peptide from Rsa1p. As expected, the overall conformation of Snu13p is retained in the complex, but some residues experience significant chemical shift perturbations, an indicator of local conformational changes upon interaction with Rsa1p and Hit1p.Besides structural and conformational details, we could obtain the spectroscopic fingerprint of this complex, setting the basis for further studies, which will involve other partners of Snu13p:Rsa1p:Hit1p, as snoRNA.
Consulter en ligne
Suggestions
Du même auteur
