Prp19/Pso4 Is an Autoinhibited Ubiquitin Ligase Activated by Stepwise Assembly of Three Splicing Factors

Mol Cell. 2018 Mar 15;69(6):979-992.e6. doi: 10.1016/j.molcel.2018.02.022.

Abstract

Human nineteen complex (NTC) acts as a multimeric E3 ubiquitin ligase in DNA repair and splicing. The transfer of ubiquitin is mediated by Prp19-a homotetrameric component of NTC whose elongated coiled coils serve as an assembly axis for two other proteins called SPF27 and CDC5L. We find that Prp19 is inactive on its own and have elucidated the structural basis of its autoinhibition by crystallography and mutational analysis. Formation of the NTC core by stepwise assembly of SPF27, CDC5L, and PLRG1 onto the Prp19 tetramer enables ubiquitin ligation. Protein-protein crosslinking of NTC, functional assays in vitro, and assessment of its role in DNA damage response provide mechanistic insight into the organization of the NTC core and the communication between PLRG1 and Prp19 that enables E3 activity. This reveals a unique mode of regulation for a complex E3 ligase and advances understanding of its dynamics in various cellular pathways.

Keywords: DNA damage response; E3 ubiquitin ligase; Prp19/NTC complex; pre-mRNA splicing.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Cell Cycle Proteins / metabolism
  • Crystallization
  • DNA Damage
  • DNA Repair Enzymes / chemistry
  • DNA Repair Enzymes / genetics
  • DNA Repair Enzymes / metabolism*
  • HEK293 Cells
  • HeLa Cells
  • Humans
  • Intracellular Signaling Peptides and Proteins / metabolism
  • Models, Molecular
  • Mutation
  • Neoplasm Proteins / metabolism
  • Nuclear Proteins / chemistry
  • Nuclear Proteins / genetics
  • Nuclear Proteins / metabolism*
  • Protein Conformation
  • RNA Splicing Factors / chemistry
  • RNA Splicing Factors / genetics
  • RNA Splicing Factors / metabolism*
  • RNA-Binding Proteins / metabolism
  • Replication Protein A / metabolism
  • Sf9 Cells
  • Spodoptera
  • Structure-Activity Relationship
  • Ubiquitination
  • WD40 Repeats

Substances

  • BCAS2 protein, human
  • CDC5L protein, human
  • Cell Cycle Proteins
  • Intracellular Signaling Peptides and Proteins
  • Neoplasm Proteins
  • Nuclear Proteins
  • PLRG1 protein, human
  • RNA Splicing Factors
  • RNA-Binding Proteins
  • RPA1 protein, human
  • Replication Protein A
  • DNA Repair Enzymes
  • PRPF19 protein, human