AID-SUN tandem of SUN1

Experimental Data Snapshot

  • Resolution: 2.20 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.183 

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This is version 1.2 of the entry. See complete history


Structural conservation of the autoinhibitory domain in SUN proteins

Xu, Y.Li, W.Ke, H.Feng, W.

(2018) Biochem Biophys Res Commun 496: 1337-1343

  • DOI: https://doi.org/10.1016/j.bbrc.2018.02.015

  • PubMed Abstract: 

    LINC complexes span across the nuclear envelope and are assembled by SUN and KASH proteins. SUN1 and SUN2 are the two most abundant SUN proteins in mammals. In SUN2, the predicted coiled-coil domain preceding the SUN domain forms a three-helix bundle that constitutes an autoinhibitory domain (AID) to lock down the SUN domain. Here, we found that SUN1 also contains an AID preceding the SUN domain and solved the structure of the AID-SUN tandem of SUN1. SUN1 AID also adopts a three-helix bundle conformation that interacts with the SUN domain and keeps it in an autoinhibited state. Disruptions of the interaction interface in the AID-SUN tandem restored the SUN domain activity for binding to the KASH peptide. Structural comparison further demonstrated that the autoinhibited conformations of the AID-SUN tandems from SUN1 and SUN2 are similar and the intramolecular interdomain packing in SUN1 is slightly more compact than that in SUN2 due to minor variations of the residues in the interaction interface. Thus, AID is a conserved functional domain in SUN proteins and this work provides the structural evidence to support the conversation of the AID-mediated autoinhibition of SUN proteins.

  • Organizational Affiliation

    National Laboratory of Biomacromolecules, CAS Center for Excellence in Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, China; University of Chinese Academy of Sciences, Beijing 100049, China.

Find similar proteins by:  (by identity cutoff)  |  3D Structure
Entity ID: 1
MoleculeChains Sequence LengthOrganismDetailsImage
SUN domain-containing protein 1242Mus musculusMutation(s): 0 
Gene Names: Sun1Unc84a
UniProt & NIH Common Fund Data Resources
Find proteins for Q9D666 (Mus musculus)
Explore Q9D666 
Go to UniProtKB:  Q9D666
IMPC:  MGI:1924303
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ9D666
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 2.20 Å
  • R-Value Free: 0.222 
  • R-Value Work: 0.181 
  • R-Value Observed: 0.183 
  • Space Group: P 31 2 1
Unit Cell:
Length ( Å )Angle ( ˚ )
a = 73.636α = 90
b = 73.636β = 90
c = 97.456γ = 120
Software Package:
Software NamePurpose
HKL-2000data reduction
HKL-2000data scaling
PDB_EXTRACTdata extraction

Structure Validation

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Entry History & Funding Information

Deposition Data

Funding OrganizationLocationGrant Number
National Key R&D Program of ChinaChina2017YFA0503501

Revision History  (Full details and data files)

  • Version 1.0: 2018-02-21
    Type: Initial release
  • Version 1.1: 2018-02-28
    Changes: Database references
  • Version 1.2: 2023-11-22
    Changes: Data collection, Database references, Refinement description