Biological Assembly 1  

 3D View: Structure

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Hetero 2-mer - A1B 

Biological assembly 1 generated by PISA (software)

Biological Assembly Evidence: gel filtration

Macromolecule Content

• Total Structure Weight: 386.62 kDa 
• Atom Count: 20491 
• Residue Count: 2621 
• Unique protein chains: 2

6EZ8

Human Huntingtin-HAP40 complex structure

• DOI: 10.2210/pdb6EZ8/pdb
• EMDataResource: EMD-3984

• Classification: PROTEIN BINDING
• Organism(s): Homo sapiens
• Expression System: Homo sapiens
• Mutation(s): No 


• Deposited: 2017-11-14 Released: 2018-02-21 
• Deposition Author(s): Guo, Q., Bin, H., Cheng, J., Pfeifer, G., Baumeister, W., Fernandez-Busnadiego, R., Kochanek, S.
• Funding Organization(s): European Commission, CHDI, CHDI foundation

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 4.00 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

The cryo-electron microscopy structure of huntingtin.

Guo, Q., Cheng, J., Seefelder, M., Engler, T., Pfeifer, G., Oeckl, P., Otto, M., Moser, F., Maurer, M., Pautsch, A., Baumeister, W., Fernandez-Busnadiego, R., Kochanek, S.

(2018) Nature 555: 117-120

• PubMed: 29466333 
• DOI: 10.1038/nature25502
• Structures With Same Primary Citation


• PubMed Abstract: 
  

Huntingtin (HTT) is a large (348 kDa) protein that is essential for embryonic development and is involved in diverse cellular activities such as vesicular transport, endocytosis, autophagy and the regulation of transcription. Although an integrative understanding of the biological functions of HTT is lacking, the large number of identified HTT interactors suggests that it serves as a protein-protein interaction hub. Furthermore, Huntington's disease is caused by a mutation in the HTT gene, resulting in a pathogenic expansion of a polyglutamine repeat at the amino terminus of HTT. However, only limited structural information regarding HTT is currently available. Here we use cryo-electron microscopy to determine the structure of full-length human HTT in a complex with HTT-associated protein 40 (HAP40; encoded by three F8A genes in humans) to an overall resolution of 4 Å. HTT is largely α-helical and consists of three major domains. The amino- and carboxy-terminal domains contain multiple HEAT (huntingtin, elongation factor 3, protein phosphatase 2A and lipid kinase TOR) repeats arranged in a solenoid fashion. These domains are connected by a smaller bridge domain containing different types of tandem repeats. HAP40 is also largely α-helical and has a tetratricopeptide repeat-like organization. HAP40 binds in a cleft and contacts the three HTT domains by hydrophobic and electrostatic interactions, thereby stabilizing the conformation of HTT. These data rationalize previous biochemical results and pave the way for improved understanding of the diverse cellular functions of HTT.

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Organizational Affiliation: 

Department of Gene Therapy, Ulm University, 89081 Ulm, Germany.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details
Huntingtin	A	3138	Homo sapiens	Mutation(s): 0  Gene Names: HTT, HD, IT15
Find proteins for P42858 (Homo sapiens) Explore P42858  Go to UniProtKB:  P42858
NIH Common Fund Data Resources
PHAROS  P42858 GTEx  ENSG00000197386

Entity ID: 2
Molecule	Chains	Sequence Length	Organism	Details
Factor VIII intron 22 protein	B	371	Homo sapiens	Mutation(s): 0  Gene Names: F8A1, F8A, F8A2, F8A3
Find proteins for P23610 (Homo sapiens) Explore P23610  Go to UniProtKB:  P23610
NIH Common Fund Data Resources
PHAROS  P23610 GTEx  ENSG00000274791GTEx  ENSG00000277203GTEx  ENSG00000277150

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 4.00 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2017-11-14 
• Released Date: 2018-02-21 
Deposition Author(s): Guo, Q., Bin, H., Cheng, J., Pfeifer, G., Baumeister, W., Fernandez-Busnadiego, R., Kochanek, S.

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Funding Organization	Location	Grant Number
European Commission	Germany	FP7 GA ERC-2012-SyG_318987-ToPAG
CHDI	United States	A12302
CHDI foundation	Germany	--

Revision History 

• Version 1.0: 2018-02-21
  Type: Initial release
  
• Version 1.1: 2018-03-07
  Changes: Database references, Other
• Version 2.0: 2018-03-28
  Changes: Advisory, Atomic model, Data collection, Database references, Derived calculations, Polymer sequence, Source and taxonomy, Structure summary
• Version 2.1: 2019-12-11
  Changes: Other