Biological Assembly 1  

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

Global Symmetry: Cyclic - C4  (3D View)
Global Stoichiometry: Homo 4-mer - A4 

Biological assembly 1 assigned by authors and generated by PISA (software)

Biological Assembly Evidence: cross-linking

Macromolecule Content

• Total Structure Weight: 214.05 kDa 
• Atom Count: 12368 
• Modelled Residue Count: 1552 
• Deposited Residue Count: 1912 
• Unique protein chains: 1

6C70

Cryo-EM structure of Orco

• PDB DOI: 10.2210/pdb6C70/pdb
• EM Map EMD-7352: EMDB EMDataResource

• Classification: MEMBRANE PROTEIN
• Organism(s): Apocrypta bakeri
• Expression System: Homo sapiens
• Mutation(s): No 
• Membrane Protein: Yes  OPMPDBTMMemProtMDmpstruc


• Deposited: 2018-01-19 Released: 2018-08-22 
• Deposition Author(s): Butterwick, J.A., Kim, K.H., Walz, T., Ruta, V.
• Funding Organization(s): National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)

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Experimental Data Snapshot

• Method: ELECTRON MICROSCOPY
• Resolution: 3.50 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Literature

Cryo-EM structure of the insect olfactory receptor Orco.

Butterwick, J.A., Del Marmol, J., Kim, K.H., Kahlson, M.A., Rogow, J.A., Walz, T., Ruta, V.

(2018) Nature 560: 447-452

• PubMed: 30111839 
• DOI: 10.1038/s41586-018-0420-8
• Primary Citation of Related Structures:  
  6C70


• PubMed Abstract: 
  

The olfactory system must recognize and discriminate amongst an enormous variety of chemicals in the environment. To contend with such diversity, insects have evolved a family of odorant-gated ion channels comprised of a highly conserved co-receptor (Orco) and a divergent odorant receptor (OR) that confers chemical specificity. Here, we present the single-particle cryo-electron microscopy structure of an Orco homomer from the parasitic fig wasp Apocrypta bakeri at 3.5 Å resolution, providing structural insight into this receptor family. Orco possesses a novel channel architecture, with four subunits symmetrically arranged around a central pore that diverges into four lateral conduits that open to the cytosol. The Orco tetramer has few inter-subunit interactions within the membrane and is bound together by a small cytoplasmic anchor domain. The minimal sequence conservation among ORs maps largely to the pore and anchor domain, shedding light on how the architecture of this receptor family accommodates its remarkable sequence diversity and facilitates the evolution of odour tuning.

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Organizational Affiliation: 

Laboratory of Neurophysiology and Behavior, The Rockefeller University, New York, NY, USA. [e-mail].

Macromolecules

Entity ID: 1
Molecule	Chains	Sequence Length	Organism	Details	Image
Odorant receptor	A, B, C, D	478	Apocrypta bakeri	Mutation(s): 0  Gene Names: Or2 Membrane Entity: Yes
UniProt
Find proteins for B0FAQ4 (Apocrypta bakeri) Explore B0FAQ4  Go to UniProtKB:  B0FAQ4

Experimental Data & Validation

Experimental Data

• Method: ELECTRON MICROSCOPY
• Resolution: 3.50 Å
• Aggregation State: PARTICLE 
• Reconstruction Method: SINGLE PARTICLE 

Structure Validation

Entry History & Funding Information

Deposition Data

• Deposited Date: 2018-01-19 
• Released Date: 2018-08-22 
Deposition Author(s): Butterwick, J.A., Kim, K.H., Walz, T., Ruta, V.

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Funding Organization	Location	Grant Number
National Institutes of Health/National Institute Of Allergy and Infectious Diseases (NIH/NIAID)	United States	R01-AI103171

Revision History  

• Version 1.0: 2018-08-22
  Type: Initial release
  
• Version 1.1: 2018-08-29
  Changes: Data collection, Database references
• Version 1.2: 2018-09-05
  Changes: Data collection, Database references
• Version 1.3: 2019-12-18
  Changes: Author supporting evidence