DHX36 in complex with the c-Myc G-quadruplex

Experimental Data Snapshot

  • Resolution: 3.79 Å
  • R-Value Free: 0.280 
  • R-Value Work: 0.238 
  • R-Value Observed: 0.243 

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This is version 1.3 of the entry. See complete history


Structural basis of G-quadruplex unfolding by the DEAH/RHA helicase DHX36.

Chen, M.C.Tippana, R.Demeshkina, N.A.Murat, P.Balasubramanian, S.Myong, S.Ferre-D'Amare, A.R.

(2018) Nature 558: 465-469

  • DOI: https://doi.org/10.1038/s41586-018-0209-9
  • Primary Citation of Related Structures:  
    5VHA, 5VHC, 5VHD, 5VHE

  • PubMed Abstract: 

    Guanine-rich nucleic acid sequences challenge the replication, transcription, and translation machinery by spontaneously folding into G-quadruplexes, the unfolding of which requires forces greater than most polymerases can exert 1,2 . Eukaryotic cells contain numerous helicases that can unfold G-quadruplexes 3 . The molecular basis of the recognition and unfolding of G-quadruplexes by helicases remains poorly understood. DHX36 (also known as RHAU and G4R1), a member of the DEAH/RHA family of helicases, binds both DNA and RNA G-quadruplexes with extremely high affinity 4-6 , is consistently found bound to G-quadruplexes in cells 7,8 , and is a major source of G-quadruplex unfolding activity in HeLa cell lysates 6 . DHX36 is a multi-functional helicase that has been implicated in G-quadruplex-mediated transcriptional and post-transcriptional regulation, and is essential for heart development, haematopoiesis, and embryogenesis in mice 9-12 . Here we report the co-crystal structure of bovine DHX36 bound to a DNA with a G-quadruplex and a 3' single-stranded DNA segment. We show that the N-terminal DHX36-specific motif folds into a DNA-binding-induced α-helix that, together with the OB-fold-like subdomain, selectively binds parallel G-quadruplexes. Comparison with unliganded and ATP-analogue-bound DHX36 structures, together with single-molecule fluorescence resonance energy transfer (FRET) analysis, suggests that G-quadruplex binding alone induces rearrangements of the helicase core; by pulling on the single-stranded DNA tail, these rearrangements drive G-quadruplex unfolding one residue at a time.

  • Organizational Affiliation

    Biochemistry and Biophysics Center, National Heart, Lung and Blood Institute, Bethesda, MD, USA.


Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
DEAH (Asp-Glu-Ala-His) box polypeptide 36933Bos taurusMutation(s): 0 
Find proteins for Q05B79 (Bos taurus)
Explore Q05B79 
Go to UniProtKB:  Q05B79
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ05B79
Sequence Annotations
  • Reference Sequence

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Entity ID: 2
MoleculeChains LengthOrganismImage
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 3.79 Å
  • R-Value Free: 0.280 
  • R-Value Work: 0.238 
  • R-Value Observed: 0.243 
  • Space Group: P 21 21 21
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 72.526α = 90
b = 79.282β = 90
c = 212.077γ = 90
Software Package:
Software NamePurpose
HKL-2000data scaling
HKL-2000data reduction

Structure Validation

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Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2018-06-13
    Type: Initial release
  • Version 1.1: 2018-06-27
    Changes: Data collection, Database references
  • Version 1.2: 2018-07-04
    Changes: Data collection, Database references
  • Version 1.3: 2023-10-04
    Changes: Data collection, Database references, Derived calculations, Refinement description