Biological Assembly 1  

 3D View: Structure | 1D-3D View | Electron Density | Validation Report

Global Symmetry: Asymmetric - C1 
Global Stoichiometry: Monomer - A1 

Biological assembly 1 assigned by authors.

Macromolecule Content

• Total Structure Weight: 19.15 kDa 
• Atom Count: 1259 
• Modelled Residue Count: 147 
• Deposited Residue Count: 176 
• Unique protein chains: 1

1KHI

CRYSTAL STRUCTURE OF HEX1

• PDB DOI: 10.2210/pdb1KHI/pdb

• Classification: STRUCTURAL PROTEIN
• Organism(s): Neurospora crassa
• Expression System: Escherichia coli
• Mutation(s): No 


• Deposited: 2001-11-30 Released: 2002-11-30 
• Deposition Author(s): Yuan, P., Swaminathan, K.

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Experimental Data Snapshot

• Method: X-RAY DIFFRACTION
• Resolution: 1.78 Å
• R-Value Free: 0.239 
• R-Value Work: 0.198 
• R-Value Observed: 0.198 

Literature

A HEX-1 crystal lattice required for Woronin body function in Neurospora crassa

Yuan, P., Jedd, G., Kumaran, D., Swaminathan, S., Shio, H., Hewitt, D., Chua, N.-H., Swaminathan, K.

(2003) Nat Struct Biol 10: 264-270

• PubMed: 12640443 
• DOI: 10.1038/nsb910
• Primary Citation of Related Structures:  
  1KHI


• PubMed Abstract: 
  

The Woronin body is a dense-core vesicle specific to filamentous ascomycetes (Euascomycetes), where it functions to seal the septal pore in response to cellular damage. The HEX-1 protein self-assembles to form this solid core of the vesicle. Here, we solve the crystal structure of HEX-1 at 1.8 A, which provides the structural basis of its self-assembly. The structure reveals the existence of three intermolecular interfaces that promote the formation of a three-dimensional protein lattice. Consistent with these data, self-assembly is disrupted by mutations in intermolecular contact residues and expression of an assembly-defective HEX-1 mutant results in the production of aberrant Woronin bodies, which possess a soluble noncrystalline core. This mutant also fails to complement a hex-1 deletion in Neurospora crassa, demonstrating that the HEX-1 protein lattice is required for Woronin body function. Although both the sequence and the tertiary structure of HEX-1 are similar to those of eukaryotic initiation factor 5A (eIF-5A), the amino acids required for HEX-1 self-assembly and peroxisomal targeting are absent in eIF-5A. Thus, we propose that a new function has evolved following duplication of an ancestral eIF-5A gene and that this may define an important step in fungal evolution.

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Related Citations: 

• A new self-assembled peroxisomal vesicle required for efficient resealing of the plasma membrane
  Jedd, G., Chua, N.-H.
  (2000) Nat Cell Biol 2: 226

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Organizational Affiliation: 

Institute of Molecular and Cell Biology, 30 Medical Drive, The National University of Singapore, Singapore, 117609.

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Hex1	A	176	Neurospora crassa	Mutation(s): 0
UniProt
Find proteins for P87252 (Neurospora crassa (strain ATCC 24698 / 74-OR23-1A / CBS 708.71 / DSM 1257 / FGSC 987)) Explore P87252  Go to UniProtKB:  P87252

Experimental Data & Validation

Experimental Data

• Method: X-RAY DIFFRACTION
• Resolution: 1.78 Å
• R-Value Free: 0.239 
• R-Value Work: 0.198 
• R-Value Observed: 0.198 
• Space Group: P 6₅ 2 2

Unit Cell:

Length ( Å )	Angle ( ˚ )
a = 57.427	α = 90
b = 57.427	β = 90
c = 196.975	γ = 120

Software Package:

Software Name	Purpose
DENZO	data reduction
SCALEPACK	data scaling
SOLVE	phasing
CNS	refinement

Structure Validation

Entry History 

Deposition Data

• Deposited Date: 2001-11-30 
• Released Date: 2002-11-30 
Deposition Author(s): Yuan, P., Swaminathan, K.

Revision History  

• Version 1.0: 2002-11-30
  Type: Initial release
  
• Version 1.1: 2008-04-27
  Changes: Version format compliance
• Version 1.2: 2011-07-13
  Changes: Version format compliance