Structural analysis reveals the flexible C-terminus of Nop15 undergoes rearrangement to recognize a pre-ribosomal RNA folding intermediate

Academic Article

Abstract

  • © The Author(s) 2016. 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 RNAbinding 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 newlyformed α helix to the distal loop where it forms protein interactions.
  • Authors

    Digital Object Identifier (doi)

    Author List

  • Zhang J; Gonzalez LE; Hall TMT
  • Start Page

  • 2829
  • End Page

  • 2837
  • Volume

  • 45
  • Issue

  • 5