7RTW

Cryo-EM structure of a TTYH3 cis-dimer


Experimental Data Snapshot

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.23 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

Structures of tweety homolog proteins TTYH2 and TTYH3 reveal a Ca 2+ -dependent switch from intra- to intermembrane dimerization.

Li, B.Hoel, C.M.Brohawn, S.G.

(2021) Nat Commun 12: 6913-6913

  • DOI: https://doi.org/10.1038/s41467-021-27283-8
  • Primary Citation of Related Structures:  
    7RTT, 7RTU, 7RTV, 7RTW

  • PubMed Abstract: 

    Tweety homologs (TTYHs) comprise a conserved family of transmembrane proteins found in eukaryotes with three members (TTYH1-3) in vertebrates. They are widely expressed in mammals including at high levels in the nervous system and have been implicated in cancers and other diseases including epilepsy, chronic pain, and viral infections. TTYHs have been reported to form Ca 2+ - and cell volume-regulated anion channels structurally distinct from any characterized protein family with potential roles in cell adhesion, migration, and developmental signaling. To provide insight into TTYH family structure and function, we determined cryo-EM structures of Mus musculus TTYH2 and TTYH3 in lipid nanodiscs. TTYH2 and TTYH3 adopt a previously unobserved fold which includes an extended extracellular domain with a partially solvent exposed pocket that may be an interaction site for hydrophobic molecules. In the presence of Ca 2+ , TTYH2 and TTYH3 form homomeric cis-dimers bridged by extracellularly coordinated Ca 2+ . Strikingly, in the absence of Ca 2+ , TTYH2 forms trans-dimers that span opposing membranes across a ~130 Å intermembrane space as well as a monomeric state. All TTYH structures lack ion conducting pathways and we do not observe TTYH2-dependent channel activity in cells. We conclude TTYHs are not pore forming subunits of anion channels and their function may involve Ca 2+ -dependent changes in quaternary structure, interactions with hydrophobic molecules near the extracellular membrane surface, and/or association with additional protein partners.


  • Organizational Affiliation

    Department of Molecular & Cell Biology, University of California, Berkeley, Berkeley, CA, 94720, USA.


Macromolecules
Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
Protein tweety homolog 3
A, B
528Mus musculusMutation(s): 0 
Gene Names: Ttyh3Kiaa1691
Membrane Entity: Yes 
UniProt & NIH Common Fund Data Resources
Find proteins for Q6P5F7 (Mus musculus)
Explore Q6P5F7 
Go to UniProtKB:  Q6P5F7
IMPC:  MGI:1925589
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ6P5F7
Glycosylation
Glycosylation Sites: 3Go to GlyGen: Q6P5F7-1
Sequence Annotations
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  • Reference Sequence
Oligosaccharides

Help

Entity ID: 2
MoleculeChains Length2D Diagram Glycosylation3D Interactions
beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose
C, D, E, G
3N/AN-Glycosylation
Glycosylation Resources
GlyTouCan:  G15407YE
GlyCosmos:  G15407YE
GlyGen:  G15407YE
Entity ID: 3
MoleculeChains Length2D Diagram Glycosylation3D Interactions
2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose
F
2N/AN-Glycosylation
Glycosylation Resources
GlyTouCan:  G42666HT
GlyCosmos:  G42666HT
GlyGen:  G42666HT
Experimental Data & Validation

Experimental Data

  • Method: ELECTRON MICROSCOPY
  • Resolution: 3.23 Å
  • Aggregation State: PARTICLE 
  • Reconstruction Method: SINGLE PARTICLE 

Structure Validation

View Full Validation Report



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
National Institutes of Health/National Institute of General Medical Sciences (NIH/NIGMS)United StatesGM123496

Revision History  (Full details and data files)

  • Version 1.0: 2021-08-25
    Type: Initial release
  • Version 1.1: 2022-03-09
    Changes: Database references