Helical reconstruction of ACAP1(BAR-PH domain) decorated membrane tubules by cryo-electron microscopy

Experimental Data Snapshot

  • Resolution: 15.0 Å
  • Aggregation State: HELICAL ARRAY 
  • Reconstruction Method: HELICAL 

Starting Model: experimental
View more details

wwPDB Validation   3D Report Full Report

This is version 1.4 of the entry. See complete history

Re-refinement Note

A newer entry is available that reflects an alternative modeling of the original data: 5H3D


A Ph Domain in Acap1 Possesses Key Features of the Bar Domain in Promoting Membrane Curvature.

Pang, X.Fan, J.Zhang, Y.Zhang, K.Gao, B.Ma, J.Li, J.Deng, Y.Zhou, Q.Egelman, E.H.Hsu, V.W.Sun, F.

(2014) Dev Cell 31: 73

  • DOI: https://doi.org/10.1016/j.devcel.2014.08.020
  • Primary Citation of Related Structures:  
    4CKG, 4CKH, 4NSW

  • PubMed Abstract: 

    The BAR (Bin-Amphiphysin-Rvs) domain undergoes dimerization to produce a curved protein structure, which superimposes onto membrane through electrostatic interactions to sense and impart membrane curvature. In some cases, a BAR domain also possesses an amphipathic helix that inserts into the membrane to induce curvature. ACAP1 (Arfgap with Coil coil, Ankyrin repeat, and PH domain protein 1) contains a BAR domain. Here, we show that this BAR domain can neither bind membrane nor impart curvature, but instead requires a neighboring PH (Pleckstrin Homology) domain to achieve these functions. Specific residues within the PH domain are responsible for both membrane binding and curvature generation. The BAR domain adjacent to the PH domain instead interacts with the BAR domains of neighboring ACAP1 proteins to enable clustering at the membrane. Thus, we have uncovered the molecular basis for an unexpected and unconventional collaboration between PH and BAR domains in membrane bending.

  • Organizational Affiliation

    National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, 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
A, B, C, D
382Homo sapiensMutation(s): 0 
UniProt & NIH Common Fund Data Resources
Find proteins for Q15027 (Homo sapiens)
Explore Q15027 
Go to UniProtKB:  Q15027
PHAROS:  Q15027
GTEx:  ENSG00000072818 
Entity Groups  
Sequence Clusters30% Identity50% Identity70% Identity90% Identity95% Identity100% Identity
UniProt GroupQ15027
Sequence Annotations
  • Reference Sequence
Experimental Data & Validation

Experimental Data

  • Resolution: 15.0 Å
  • Aggregation State: HELICAL ARRAY 
  • Reconstruction Method: HELICAL 
EM Software:
TaskSoftware PackageVersion

Structure Validation

View Full Validation Report

Entry History 

Deposition Data

Revision History  (Full details and data files)

  • Version 1.0: 2014-10-15
    Type: Initial release
  • Version 1.1: 2014-10-22
    Changes: Database references
  • Version 1.2: 2017-08-30
    Changes: Data collection, Derived calculations, Refinement description
  • Version 1.3: 2019-01-23
    Changes: Advisory, Data collection, Derived calculations
  • Version 1.4: 2024-05-08
    Changes: Data collection, Database references, Refinement description