The dynamic nature of the human Origin Recognition Complex revealed through five cryoEM structures

  1. Matt J Jaremko
  2. Kin Fan On
  3. Dennis R Thomas
  4. Bruce Stillman
  5. Leemor Joshua-Tor  Is a corresponding author
  1. Cold Spring Harbor Laboratory/HHMI, United States
  2. Cold Spring Harbor Laboratory, United States

Abstract

Genome replication is initiated from specific origin sites established by dynamic events. The Origin Recognition Complex (ORC) is necessary for orchestrating the initiation process by binding to origin DNA, recruiting CDC6, and assembling the MCM replicative helicase on DNA. Here we report five cryoEM structures of the human ORC (HsORC) that illustrate the native flexibility of the complex. The absence of ORC1 revealed a compact, stable complex of ORC2-5. Introduction of ORC1 opens the complex into several dynamic conformations. Two structures revealed dynamic movements of the ORC1 AAA+ and ORC2 winged-helix domains that likely impact DNA incorporation into the ORC core. Additional twist and pinch motions were observed in an open ORC conformation revealing a hinge at the ORC5·3 interface that may facilitate ORC binding to DNA. Finally, a structure of ORC was determined with endogenous DNA bound in the core revealing important differences between human and yeast origin recognition.

Data availability

All coordinates and cryoEM maps have deposited in the PDB and EMDB:ORC-O1AAA:PDB code: 7JPOEMDB code: EMD-22417ORC-O2WH:PDB code: 7JPPEMDB code: EMD-22418ORC-O2-5:PDB code: 7JPQEMDB code: EMD-22419ORC-OPEN:PDB code: 7JPREMDB code: EMD-22420ORC-DNA:PDB code: 7JPSEMDB code: EMD-22421

The following data sets were generated

Article and author information

Author details

  1. Matt J Jaremko

    Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory/HHMI, Cold Spring Harbor, United States
    Competing interests
    No competing interests declared.
  2. Kin Fan On

    Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory/HHMI, Cold Spring Harbor, United States
    Competing interests
    No competing interests declared.
  3. Dennis R Thomas

    Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory, Cold Spring Harbor, United States
    Competing interests
    No competing interests declared.
  4. Bruce Stillman

    none, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY, United States
    Competing interests
    Bruce Stillman, Reviewing editor, eLife.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0002-9453-4091
  5. Leemor Joshua-Tor

    Keck Structural Biology Laboratory, Cold Spring Harbor Laboratory/HHMI, Cold Spring Harbor, United States
    For correspondence
    leemor@cshl.edu
    Competing interests
    No competing interests declared.
    ORCID icon "This ORCID iD identifies the author of this article:" 0000-0001-8185-8049

Funding

Howard Hughes Medical Institute (N/A)

  • Leemor Joshua-Tor

National Institutes of Health (F32GM129923)

  • Matt J Jaremko

National Academies of Sciences, Engineering, and Medicine (GM45436)

  • Bruce Stillman

The funders had no role in study design, data collection and interpretation, or the decision to submit the work for publication.

Reviewing Editor

  1. Sriram Subramaniam, University of British Columbia, Canada

Publication history

  1. Received: May 6, 2020
  2. Accepted: August 17, 2020
  3. Accepted Manuscript published: August 18, 2020 (version 1)
  4. Version of Record published: September 2, 2020 (version 2)

Copyright

© 2020, Jaremko et al.

This article is distributed under the terms of the Creative Commons Attribution License permitting unrestricted use and redistribution provided that the original author and source are credited.

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  1. Matt J Jaremko
  2. Kin Fan On
  3. Dennis R Thomas
  4. Bruce Stillman
  5. Leemor Joshua-Tor
(2020)
The dynamic nature of the human Origin Recognition Complex revealed through five cryoEM structures
eLife 9:e58622.
https://doi.org/10.7554/eLife.58622

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