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113  structures 1331  species 0  interactions 14117  sequences 238  architectures

Family: BAR (PF03114)

Summary: BAR domain

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This is the Wikipedia entry entitled "BAR domain". More...

BAR domain Edit Wikipedia article

BAR domain
PDB 1uru EBI.jpg
Structure of amphiphysin BAR.[1]
Bin/amphiphysin/Rvs domain
BAR domain of APPL family
EFC/F-BAR homology domain
Vps5 C terminal like (BAR domain)
WASP-binding domain of sorting nexin proteins

In molecular biology, BAR domains are highly conserved protein dimerisation domains that occur in many proteins involved in membrane dynamics in a cell. The BAR domain is banana-shaped and binds to membrane via its concave face. It is capable of sensing membrane curvature by binding preferentially to curved membranes. BAR domains are named after three proteins that they are found in: Bin, Amphiphysin and Rvs.

BAR domains occur in combinations with other domains

Many BAR family proteins contain alternative lipid specificity domains that help target these protein to particular membrane compartments. Some also have SH3 domains that bind to dynamin and thus proteins like amphiphysin and endophilin are implicated in the orchestration of vesicle scission.

N-BAR domain

Some BAR domain containing proteins have an N-terminal amphipathic helix preceding the BAR domain. This helix inserts (like in the epsin ENTH domain) into the membrane and induces curvature, which is stabilised by the BAR dimer. Amphiphysin, endophilin, BRAP1/bin2 and nadrin are examples of such proteins containing an N-BAR. The Drosophila amphiphysin N-BAR (DA-N-BAR) is an example of a protein with a preference for negatively charged surfaces.[1]

Human proteins containing this domain


F-BAR (EFC) domain

F-BAR domains (for FCH-BAR, or EFC for Extended FCH Homology) are BAR domains that are extensions of the already established FCH domain. They are frequently found at the amino terminus of proteins. They can bind lipid membranes and can tubulate lipids in vitro and in vivo, but their exact physiological role still is under investigation.[3] Examples of the F-BAR domain family are CIP4/FBP17/Toca-1, Syndapins (also called PACSINs) and muniscins. Gene knock-out of syndapin I in mice revealed that this brain-enriched isoform of the syndapin family is crucial for proper size control of synaptic vesicles and thereby indeed helps to define membrane curvature a physiological process. Work of the lab of Britta Qualmann also demonstrated that syndapin I is crucial for proper targeting of the large GTPase dynamin to membranes.[4]

Sorting nexins

The sorting nexin family of proteins includes several members that possess a BAR domain, including the well characterized SNX1 and SNX9.

Human proteins containing this domain


See also

External links


  1. ^ a b Peter BJ, Kent HM, Mills IG, et al. (January 2004). "BAR domains as sensors of membrane curvature: the amphiphysin BAR structure". Science. 303 (5657): 495–9. doi:10.1126/science.1092586. PMID 14645856. S2CID 6104655.
  2. ^ "Gene group: N-BAR domain containing". HGNC: HUGO gene nomenclature committee.
  3. ^ Qualmann B, Koch D, Kessels MM (August 2011). "Let's go bananas: revisiting the endocytic BAR code". EMBO J. 30 (17): 3501–15. doi:10.1038/emboj.2011.266. PMC 3181480. PMID 21878992.
  4. ^ Koch D, Spiwoks-Becker I, Sabanov V, Sinning A, Dugladze T, Stellmacher A, Ahuja R, Grimm J, Schüler S, Müller A, Angenstein F, Ahmed T, Diesler A, Moser M, Tom Dieck S, Spessert R, Boeckers TM, Fässler R, Hübner CA, Balschun D, Gloveli T, Kessels MM, Qualmann B (December 2011). "Proper synaptic vesicle formation and neuronal network activity critically rely on syndapin I". EMBO J. 30 (24): 4955–69. doi:10.1038/emboj.2011.339. PMC 3243622. PMID 21926968.

Further reading

This page is based on a Wikipedia article. The text is available under the Creative Commons Attribution/Share-Alike License.

This tab holds the annotation information that is stored in the Pfam database. As we move to using Wikipedia as our main source of annotation, the contents of this tab will be gradually replaced by the Wikipedia tab.

BAR domain Provide feedback

BAR domains are dimerisation, lipid binding and curvature sensing modules found in many different protein families. A BAR domain with an additional N-terminal amphipathic helix (an N-BAR) can drive membrane curvature. These N-BAR domains are found in amphiphysin, endophilin, BRAP and Nadrin. BAR domains are also frequently found alongside domains that determine lipid specificity, like PF00169 and PF00787 domains in beta centaurins and sorting nexins respectively.

Literature references

  1. Gallop JL, Butler PJ, McMahon HT; , Nature. 2005;438:675-678.: Endophilin and CtBP/BARS are not acyl transferases in endocytosis or Golgi fission. PUBMED:16319893 EPMC:16319893

  2. Peter BJ, Kent HM, Mills IG, Vallis Y, Butler PJ, Evans PR, McMahon HT; , Science. 2004;303:495-499.: BAR domains as sensors of membrane curvature: the amphiphysin BAR structure. PUBMED:14645856 EPMC:14645856

  3. Gallop JL, Jao CC, Kent HM, Butler PJ, Evans PR, Langen R, McMahon HT; , EMBO J. 2006;25:2898-2910.: Mechanism of endophilin N-BAR domain-mediated membrane curvature. PUBMED:16763559 EPMC:16763559

  4. Weissenhorn W; , J Mol Biol. 2005;351:653-661.: Crystal structure of the endophilin-A1 BAR domain. PUBMED:16023669 EPMC:16023669

Internal database links

External database links

This tab holds annotation information from the InterPro database.

InterPro entry IPR004148

Endocytosis and intracellular transport involve several mechanistic steps:

  • (1) for the internalisation of cargo molecules, the membrane needs to bend to form a vesicular structure, which requires membrane curvature and a rearrangement of the cytoskeleton;
  • (2) following its formation, the vesicle has to be pinched off the membrane;
  • (3) the cargo has to be subsequently transported through the cell and the vesicle must fuse with the correct cellular compartment.
Members of the Amphiphysin protein family are key regulators in the early steps of endocytosis, involved in the formation of clathrin-coated vesicles by promoting the assembly of a protein complex at the plasma membrane and directly assist in the induction of the high curvature of the membrane at the neck of the vesicle. Amphiphysins contain a characteristic domain, known as the BAR (Bin-Amphiphysin-Rvs)-domain, which is required for their in vivo function and their ability to tubulate membranes [ PUBMED:14993925 ].

The crystal structure of these proteins suggest the domain forms a crescent-shaped dimer of a three-helix coiled coil with a characteristic set of conserved hydrophobic, aromatic and hydrophilic amino acids. Proteins containing this domain have been shown to homodimerise, heterodimerise or, in a few cases, interact with small GTPases.

Gene Ontology

The mapping between Pfam and Gene Ontology is provided by InterPro. If you use this data please cite InterPro.

Domain organisation

Below is a listing of the unique domain organisations or architectures in which this domain is found. More...

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Pfam Clan

This family is a member of clan Golgi-transport (CL0145), which has the following description:

This clan contains families that are involved in intracellular transport and signalling. Arfaptins are proteins which interact with small GTPases involved in vesicular budding at the Golgi complex. They form an elongated dimer of three helix coiled coils and are structurally very similar to the BAR domain [1][2]. The Sec34 family is involved in tethering vesicles to the Golgi [3].

The clan contains the following 12 members:

Angiomotin_C Arfaptin BAR BAR_2 BAR_3 BAR_3_WASP_bdg BAR_4 FAM92 FCH IMD Pil1 Vps5


We store a range of different sequence alignments for families. As well as the seed alignment from which the family is built, we provide the full alignment, generated by searching the sequence database (reference proteomes) using the family HMM. We also generate alignments using four representative proteomes (RP) sets and the UniProtKB sequence database. More...

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You can also download a FASTA format file containing the full-length sequences for all sequences in the full alignment.

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HMM logos is one way of visualising profile HMMs. Logos provide a quick overview of the properties of an HMM in a graphical form. You can see a more detailed description of HMM logos and find out how you can interpret them here. More...


This page displays the phylogenetic tree for this family's seed alignment. We use FastTree to calculate neighbour join trees with a local bootstrap based on 100 resamples (shown next to the tree nodes). FastTree calculates approximately-maximum-likelihood phylogenetic trees from our seed alignment.

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Curation and family details

This section shows the detailed information about the Pfam family. You can see the definitions of many of the terms in this section in the glossary and a fuller explanation of the scoring system that we use in the scores section of the help pages.

Curation View help on the curation process

Seed source: Psi-blast P25343
Previous IDs: none
Type: Domain
Sequence Ontology: SO:0000417
Author: Bateman A , McMahon HT
Number in seed: 23
Number in full: 14117
Average length of the domain: 216.70 aa
Average identity of full alignment: 21 %
Average coverage of the sequence by the domain: 41.11 %

HMM information View help on HMM parameters

HMM build commands:
build method: hmmbuild -o /dev/null HMM SEED
search method: hmmsearch -Z 61295632 -E 1000 --cpu 4 HMM pfamseq
Model details:
Parameter Sequence Domain
Gathering cut-off 28.5 28.5
Trusted cut-off 28.5 28.5
Noise cut-off 28.4 28.4
Model length: 239
Family (HMM) version: 21
Download: download the raw HMM for this family

Species distribution

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Colour assignments

Archea Archea Eukaryota Eukaryota
Bacteria Bacteria Other sequences Other sequences
Viruses Viruses Unclassified Unclassified
Viroids Viroids Unclassified sequence Unclassified sequence


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For those sequences which have a structure in the Protein DataBank, we use the mapping between UniProt, PDB and Pfam coordinate systems from the PDBe group, to allow us to map Pfam domains onto UniProt sequences and three-dimensional protein structures. The table below shows the structures on which the BAR domain has been found. There are 113 instances of this domain found in the PDB. Note that there may be multiple copies of the domain in a single PDB structure, since many structures contain multiple copies of the same protein sequence.

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AlphaFold Structure Predictions

The list of proteins below match this family and have AlphaFold predicted structures. Click on the protein accession to view the predicted structure.

Protein Predicted structure External Information
A0A0G2K5Z4 View 3D Structure Click here
A0A0R0ER14 View 3D Structure Click here
A0A0R0FX98 View 3D Structure Click here
A0A0R4IIW2 View 3D Structure Click here
A0A0R4IS36 View 3D Structure Click here
A0A0R4IVK5 View 3D Structure Click here
A0A0R4IXA4 View 3D Structure Click here
A0A0R4IZ95 View 3D Structure Click here
A0A1D6Q297 View 3D Structure Click here
A0A1D8PEG6 View 3D Structure Click here
A0A2R8PXF2 View 3D Structure Click here
A0A2R8Q0C3 View 3D Structure Click here
A0A2R8Q349 View 3D Structure Click here
A0A2R8Q971 View 3D Structure Click here
A0A2R8QMI5 View 3D Structure Click here
A0A2R8QNY2 View 3D Structure Click here
A0A2R8QQA3 View 3D Structure Click here
A1IGU4 View 3D Structure Click here
B1H1H2 View 3D Structure Click here
B1V8A0 View 3D Structure Click here
D3Z6Q9 View 3D Structure Click here
D3ZFJ3 View 3D Structure Click here
E2RP94 View 3D Structure Click here
E7F1U2 View 3D Structure Click here
E7FD40 View 3D Structure Click here
F1LQX4 View 3D Structure Click here
F1LUU6 View 3D Structure Click here
F1QGH8 View 3D Structure Click here
F1QJB5 View 3D Structure Click here
F1QK94 View 3D Structure Click here
F1R7M1 View 3D Structure Click here
F1RAR0 View 3D Structure Click here
F1RDJ4 View 3D Structure Click here
M0R4F8 View 3D Structure Click here
O00499 View 3D Structure Click here
O08539 View 3D Structure Click here
O08838 View 3D Structure Click here
O08839 View 3D Structure Click here
O35179 View 3D Structure Click here
O35180 View 3D Structure Click here