9OF2 | pdb_00009of2

Dimer of HIF-2a-ARNT Heterodimers Complexed on 51-bp HRE/HAS


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.70 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

wwPDB Validation   3D Report Full Report


This is version 1.1 of the entry. See complete history


Literature

Context-Dependent Variability Of HIF Heterodimers Influences Interactions With Macromolecular And Small Molecule Partners.

Closson, J.D.Xu, X.Zhang, M.Tiyani, T.T.Marcelino, L.P.Isiorho, E.A.Nagati, J.S.Garcia, J.A.Gardner, K.H.

(2025) bioRxiv 

  • DOI: https://doi.org/10.1101/2025.05.29.656908
  • Primary Citation of Related Structures:  
    9OF0, 9OF2, 9OFU, 9OPF

  • PubMed Abstract: 

    Hypoxia inducible factors (HIFs) are transcription factors that coordinate cellular responses to low oxygen levels, functioning as an α/β heterodimer which binds a short hypoxia response element (HRE) DNA sequence. Prior studies suggest HIF/HRE complexes are augmented by the binding of additional factors nearby, but those interactions are not well understood. Here, we integrated structural and biochemical approaches to investigate several functionally relevant HIF assemblies with other protein, small molecule, and DNA partners. First, we used cryo-electron microscopy (cryo-EM) to establish HIF-1 and HIF-2 form novel "dimer-of-heterodimers" (DoHD) complexes on extended human EPO enhancer sequences, showing that one heterodimer bound at a canonical HRE site with the second binding in an inverted fashion to an HRE-adjacent sequence (HAS) 8 bp away. Consistent with ARNT PAS-B domains predominating interactions within a DoHD, we found HIF-1 and HIF-2 assemble mixed DoHD complexes on the same DNA. Second, we saw substantial variability among ligands for isolated ARNT or HIF-2α PAS-B domains to bind larger complexes: for example, the ARNT PAS-B binding KG-548 and KG-279 ligands both bound the simpler HIF-2 heterodimer but exhibited differential binding to a HIF-2 DoHD. Finally, we combined cryo-EM and hydrogen-deuterium exchange by mass spectrometry (HDX-MS) to show how HIF-1 and HIF-2 heterodimers engage the transforming acidic coiled-coil containing protein 3 (TACC3) coactivator via both ARNT and HIF-α subunits, though this was unseen in the larger DoHD. Our findings highlight the importance of both molecular context and dynamics in biomolecular complex formation, adding to the complexities of potential regulation.


  • Organizational Affiliation

    Structural Biology Initiative, CUNY Advanced Science Research Center, New York, NY 10031.


Macromolecules

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 3
MoleculeChains Sequence LengthOrganismDetailsImage
Endothelial PAS domain-containing protein 1
C, E
372Homo sapiensMutation(s): 0 
Gene Names: EPAS1BHLHE73HIF2AMOP2PASD2
UniProt & NIH Common Fund Data Resources
Find proteins for Q99814 (Homo sapiens)
Explore Q99814 
Go to UniProtKB:  Q99814
PHAROS:  Q99814
GTEx:  ENSG00000116016 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ99814
Sequence Annotations
Expand
  • Reference Sequence
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 4
MoleculeChains Sequence LengthOrganismDetailsImage
Aryl hydrocarbon receptor nuclear translocator
D, F
381Homo sapiensMutation(s): 0 
Gene Names: ARNTBHLHE2
UniProt & NIH Common Fund Data Resources
Find proteins for P27540 (Homo sapiens)
Explore P27540 
Go to UniProtKB:  P27540
PHAROS:  P27540
GTEx:  ENSG00000143437 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupP27540
Sequence Annotations
Expand
  • Reference Sequence
Find similar nucleic acids by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains LengthOrganismImage
51-nt Hypoxia Response Element (Forward)51Homo sapiens
Sequence Annotations
Expand
  • Reference Sequence
Find similar nucleic acids by:  (by identity cutoff)  |  3D Structure
Entity ID: 2
MoleculeChains LengthOrganismImage
51-nt Hypoxia Response Element (Reverse)51Homo sapiens
Sequence Annotations
Expand
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.70 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 
EM Software:
TaskSoftware PackageVersion
MODEL REFINEMENTPHENIX1.20.1_4487
MODEL REFINEMENTCoot0.9.6.1.1
RECONSTRUCTIONcryoSPARC4.7.0

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Cancer Institute (NIH/NCI)United StatesU54 CA132378
National Institutes of Health/National Cancer Institute (NIH/NCI)United StatesU54 C137788
The G. Harold and Leila Y. Mathers FoundationUnited StatesMF-2112-02288

Revision History  (Full details and data files)

  • Version 1.0: 2025-06-11
    Type: Initial release
  • Version 1.1: 2025-06-25
    Changes: Data collection, Database references