The Bin/Amphiphysin/Rvs (BAR) domain, a dimerization module that binds membranes and detects membrane curvature; BAR domains are dimerization, lipid binding and curvature sensing modules found in many different proteins with diverse functions including organelle biogenesis, membrane trafficking or remodeling, and cell division and migration. Mutations in BAR containing proteins have been linked to diseases and their inactivation in cells leads to altered membrane dynamics. A BAR domain with an additional N-terminal amphipathic helix (an N-BAR) can drive membrane curvature. These N-BAR domains are found in amphiphysins and endophilins, among others. BAR domains are also frequently found alongside domains that determine lipid specificity, such as the Pleckstrin Homology (PH) and Phox Homology (PX) domains which are present in beta centaurins (ACAPs and ASAPs) and sorting nexins, respectively. A FES-CIP4 Homology (FCH) domain together with a coiled coil region is called the F-BAR domain and is present in Pombe/Cdc15 homology (PCH) family proteins, which include Fes/Fes tyrosine kinases, PACSIN or syndapin, CIP4-like proteins, and srGAPs, among others. The Inverse (I)-BAR or IRSp53/MIM homology Domain (IMD) is found in multi-domain proteins, such as IRSp53 and MIM, that act as scaffolding proteins and transducers of a variety of signaling pathways that link membrane dynamics and the underlying actin cytoskeleton. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. The I-BAR domain induces membrane protrusions in the opposite direction compared to classical BAR and F-BAR domains, which produce membrane invaginations. BAR domains that also serve as protein interaction domains include those of arfaptin and OPHN1-like proteins, among others, which bind to Rac and Rho GAP domains, respectively.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374  53 DADLDAKLELFHSIQRTCLDLSKAIVLYQKRICFLSQEENELGKFLRSQGFQDKTRAGKMMQATGKALCFSSQQRLALRN 132
Cdd:cd07661     1 DAELDAKLELFRSVQDTCLELLKIIDNYQERLCILSQEENVLGKFLKEQGKIDKTTAGKMMAATGKALSFSSQQRLALRV 80

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1185542374 133 PLCRFHQEVETFRHRAISDTWLTVNRMEQCRTEYRGALLWMKDVSQELDPDLYKQMEKFRK 193
Cdd:cd07661    81 PLLRLYQEVETFRERAIADTLQTIQRMEKCRTEYRAALLWMKSVSQELDPDTYKQLEKFRK 141

The Bin/Amphiphysin/Rvs (BAR) domain of Islet Cell Autoantigen 69-kDa; The BAR domain of Arfaptin-like proteins, also called the Arfaptin domain, is a dimerization and lipid binding module that can detect and drive membrane curvature. Islet cell autoantigen 69-kDa (ICA69) is a diabetes-associated autoantigen that is highly expressed in brain and beta cells. It is involved in membrane trafficking at the Golgi complex in neurosecretory cells. It is coexpressed with Protein Interacting with C Kinase 1 (PICK1), also a the BAR domain containing protein, in many tissues at different developmental stages. In neurons, ICA69 colocalizes with PICK1 in cell bodies and dendrites but is absent in synapses where PICK1 is enriched. ICA69 contains an N-terminal BAR domain and a conserved C-terminal domain of unknown function. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. ICA69 associates with PICK1 through their BAR domains to form a heterodimer which is involved in regulating the synaptic targeting and surface expression of AMPA receptors. Autoantibodies against ICA69 have been identified in patients with insulin-dependent diabetes mellitus, rheumatoid arthritis, and primary Sjogren's syndrome. ICA69 has also been shown to be released by pancreatic cancer cells.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374  53 DADLDAKLELFHSIQRTCLDLSKAIVLYQKRICFLSQEENELGKFLRSQGFQDKTRAGKMMQATGKALCFSSQQRLALRN 132
Cdd:cd07661     1 DAELDAKLELFRSVQDTCLELLKIIDNYQERLCILSQEENVLGKFLKEQGKIDKTTAGKMMAATGKALSFSSQQRLALRV 80

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1185542374 133 PLCRFHQEVETFRHRAISDTWLTVNRMEQCRTEYRGALLWMKDVSQELDPDLYKQMEKFRK 193
Cdd:cd07661    81 PLLRLYQEVETFRERAIADTLQTIQRMEKCRTEYRAALLWMKSVSQELDPDTYKQLEKFRK 141

Arfaptin-like domain; Arfaptin interacts with ARF1, a small GTPase involved in vesicle budding at the Golgi complex and immature secretory granules. The structure of arfaptin shows that upon binding to a small GTPase, arfaptin forms an elongated, crescent-shaped dimer of three-helix coiled-coils. The N-terminal region of ICA69 is similar to arfaptin.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374  44 KEDEHVVASDADLDAKLELFHSIQRTCLDLSKAIVLYQKRICFLSQEENELGKFLRSQGFQDKTRA-GKMMQATGKALCF 122
Cdd:pfam06456   1 KEDSHAITSDDELDAKLEVLRSIQRTYLGLVKLARNYSKRLYDLSQTQKELGDFFKDLGKHEKQQAaGEAFTAFGETHRF 80

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1185542374 123 SSQQRLALRNPLCRFHQEVETFRHRAISDTWLTVNRMEQCRTEYRGALLWMKDVSQELDPDLYKQMEKFRKS 194
Cdd:pfam06456  81 LAKQGLALLVPLNRFISSVNTFVNKAIPDTLLTIKRYEDARTEYRAYLLWMKEASDELDPDVAKQMPKFRVA 152

The Bin/Amphiphysin/Rvs (BAR) domain of Islet Cell Autoantigen 69-kDa; The BAR domain of Arfaptin-like proteins, also called the Arfaptin domain, is a dimerization and lipid binding module that can detect and drive membrane curvature. Islet cell autoantigen 69-kDa (ICA69) is a diabetes-associated autoantigen that is highly expressed in brain and beta cells. It is involved in membrane trafficking at the Golgi complex in neurosecretory cells. It is coexpressed with Protein Interacting with C Kinase 1 (PICK1), also a the BAR domain containing protein, in many tissues at different developmental stages. In neurons, ICA69 colocalizes with PICK1 in cell bodies and dendrites but is absent in synapses where PICK1 is enriched. ICA69 contains an N-terminal BAR domain and a conserved C-terminal domain of unknown function. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions. ICA69 associates with PICK1 through their BAR domains to form a heterodimer which is involved in regulating the synaptic targeting and surface expression of AMPA receptors. Autoantibodies against ICA69 have been identified in patients with insulin-dependent diabetes mellitus, rheumatoid arthritis, and primary Sjogren's syndrome. ICA69 has also been shown to be released by pancreatic cancer cells.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374  53 DADLDAKLELFHSIQRTCLDLSKAIVLYQKRICFLSQEENELGKFLRSQGFQDKTRAGKMMQATGKALCFSSQQRLALRN 132
Cdd:cd07661     1 DAELDAKLELFRSVQDTCLELLKIIDNYQERLCILSQEENVLGKFLKEQGKIDKTTAGKMMAATGKALSFSSQQRLALRV 80

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|.
gi 1185542374 133 PLCRFHQEVETFRHRAISDTWLTVNRMEQCRTEYRGALLWMKDVSQELDPDLYKQMEKFRK 193
Cdd:cd07661    81 PLLRLYQEVETFRERAIADTLQTIQRMEKCRTEYRAALLWMKSVSQELDPDTYKQLEKFRK 141

Arfaptin-like domain; Arfaptin interacts with ARF1, a small GTPase involved in vesicle budding at the Golgi complex and immature secretory granules. The structure of arfaptin shows that upon binding to a small GTPase, arfaptin forms an elongated, crescent-shaped dimer of three-helix coiled-coils. The N-terminal region of ICA69 is similar to arfaptin.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374  44 KEDEHVVASDADLDAKLELFHSIQRTCLDLSKAIVLYQKRICFLSQEENELGKFLRSQGFQDKTRA-GKMMQATGKALCF 122
Cdd:pfam06456   1 KEDSHAITSDDELDAKLEVLRSIQRTYLGLVKLARNYSKRLYDLSQTQKELGDFFKDLGKHEKQQAaGEAFTAFGETHRF 80

                          90       100       110       120       130       140       150
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|..
gi 1185542374 123 SSQQRLALRNPLCRFHQEVETFRHRAISDTWLTVNRMEQCRTEYRGALLWMKDVSQELDPDLYKQMEKFRKS 194
Cdd:pfam06456  81 LAKQGLALLVPLNRFISSVNTFVNKAIPDTLLTIKRYEDARTEYRAYLLWMKEASDELDPDVAKQMPKFRVA 152

The Bin/Amphiphysin/Rvs (BAR) domain of Arfaptin-like proteins, a dimerization module that binds and bends membranes; The BAR domain of Arfaptin-like proteins, also called the Arfaptin domain, is a dimerization, lipid binding and curvature sensing module present in Arfaptins, PICK1, ICA69, and similar proteins. Arfaptins are ubiquitously expressed proteins implicated in mediating cross-talk between Rac, a member of the Rho family GTPases, and Arf (ADP-ribosylation factor) small GTPases. Arfaptins bind to GTP-bound Arf1, Arf5, and Arf6, with strongest binding to GTP-Arf1. Arfaptins also binds to Rac-GTP and Rac-GDP with similar affinities. The Arfs are thought to bind to the same surface as Rac, and their binding is mutually exclusive. Protein Interacting with C Kinase 1 (PICK1) plays a key role in the trafficking of AMPA receptors, which are critical for regulating synaptic strength and may be important in cellular processes involved in learning and memory. Islet cell autoantigen 69-kDa (ICA69) is a diabetes-associated autoantigen that is involved in membrane trafficking at the Golgi complex in neurosecretory cells. ICA69 associates with PICK1 through their BAR domains to form a heterodimer which is involved in regulating the synaptic targeting and surface expression of AMPA receptors. BAR domains form dimers that bind to membranes, induce membrane bending and curvature, and may also be involved in protein-protein interactions.

                          10        20        30        40        50        60        70        80
                  ....*....|....*....|....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374  53 DADLDAKLELFHSIQRTCLDLSKAIVLYQKRICFLSQEENELGKFLRSQGFQDKTRAGKMMQATGKALCFSSQQRLALRN 132
Cdd:cd00011     1 DLELELQLELLRETKRKYESVLQLGRALTAHLYSLSQTQHALGDAFADLSQKDPELAGEEFGYNAEAQKLLCKNGETLLG 80

                          90       100       110       120       130       140
                  ....*....|....*....|....*....|....*....|....*....|....*....|
gi 1185542374 133 PLCRFHQEVETFRHRAISDTWLTVNRMEQCRTEYRGALLWMKDVSQELDPDLYKQMEKFR 192
Cdd:cd00011    81 AVNFFVSSINTLVTKAIEDTLLTVKQYEAARLEYDAYRLDLKELSLEPRDDTAGTRGRLR 140