title: Structural analysis reveals the flexible C-terminus of Nop15 undergoes rearrangement to recognize a pre-ribosomal RNA folding intermediate.
abstract: The RNA recognition motif (RRM) is the most abundant RNA-binding domain in eukaryotes, and it plays versatile roles in RNA metabolism. Despite its abundance, diversity of RRM structure and function is generated by variations on a conserved core. Yeast Nop15 is an RRM protein that is essential for large ribosomal subunit biogenesis. We determined a 2.0 Å crystal structure of Nop15 that reveals a C-terminal α-helical region obscures its canonical RNA-binding surface. Small-angle X-ray scattering, NMR and RNA-binding analyses further reveal that the C-terminal residues of Nop15 are highly flexible, but essential for tight RNA binding. Moreover, comparison with a recently reported cryo-electron microscopy structure indicates that dramatic rearrangement of the C-terminal region of Nop15 in the pre-ribosome exposes the RNA-binding surface to recognize the base of its stem-loop target RNA and extends a newly-formed α helix to the distal loop where it forms protein interactions.
authors: Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, P.O. Box 12233, MD F3-05, Research Triangle Park, NC 27709, USA.
authors: Jun
authors: J
authors: Zhang
authors: Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, P.O. Box 12233, MD F3-05, Research Triangle Park, NC 27709, USA.
authors: Lauren E
authors: LE
authors: Gonzalez
authors: Epigenetics and Stem Cell Biology Laboratory, National Institute of Environmental Health Sciences, National Institutes of Health, P.O. Box 12233, MD F3-05, Research Triangle Park, NC 27709, USA.
authors: Traci M Tanaka
authors: TMT
authors: Hall
mesh_terms: D001665:Binding Sites; D011485:Protein Binding; D058849:Protein Refolding; D059370:RNA Folding; D012322:RNA Precursors / Q000737:chemistry / Q000378:metabolism; D000071377:RNA Recognition Motif; D012335:RNA, Ribosomal / Q000737:chemistry* / Q000378:metabolism; D012269:Ribosomal Proteins / Q000737:chemistry* / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000737:chemistry* / Q000378:metabolism
chemical_list: C568702:Nop15 protein, S cerevisiae; D012322:RNA Precursors; D012335:RNA, Ribosomal; D012269:Ribosomal Proteins; D029701:Saccharomyces cerevisiae Proteins