endophilin-A1; EEN-B1; endophilin-1; SH3 domain protein 2A; SH3 domain-containing GRB2-like protein 2 (SH3GL2, CNSA2, SH3D2A)

Function

• implicated in synaptic vesicle endocytosis
• may recruit other proteins to membranes with high curvature
• monomer; in cytoplasm homodimer; when associated with membranes (putative)
• interacts with OPHN1
• interacts with SYNJ1 & DNM1
• interacts with MAP4K3; the interaction appears to regulate MAP4K3-mediated JNK activation
• interacts with PDCD6IP
• interacts with synaptojanin & dynamin 1
• role in synaptic vesicle recycling

Structure

• an N-terminal amphipathic helix, the BAR domain & a 2nd amphipathic helix inserted into helix 1 of the BAR domain (N-BAR domain) induce membrane curvature & bind curved membranes
• the BAR domain dimer forms a rigid crescent shaped bundle of helices with the pair of second amphipathic helices protruding towards the membrane-binding surface
• belongs to the endophilin family
• contains 1 BAR domain
• contains 1 SH3 domain

Compartment

• cytoplasm, membrane; peripheral membrane
• concentrated in presynaptic nerve terminals in neurons

Expression

• expressed in brain, mostly in frontal cortex
• expressed at high level in fetal cerebellum

Notes

• HeLa cells expressing the N-BAR domain of SH3GL2 show tubulation of the plasma membrane
• the N-BAR domain binds liposomes & induces formation of tubules from liposomes
• the N-terminal amphipathic helix is required for liposome binding.
• the second amphipathic helix enhances liposome tubulation

More general terms

• endophilin family protein

Database

• Entrez gene: http://www.ncbi.nlm.nih.gov/sites/entrez?db=gene&cmd=Retrieve&dopt=Graphics&list_uids=6456
• Kegg: http://www.genome.jp/dbget-bin/www_bget?hsa:6456
• OMIM: https://mirror.omim.org/entry/604465
• UniProt: http://www.uniprot.org/uniprot/Q99962.html