SH3GLB1
Domain
An N-terminal amphipathic helix, the BAR domain and a second amphipathic helix inserted into helix 1 of the BAR domain (N-BAR domain) induce membrane curvature and bind curved membranes.
The SH3 domain is required and sufficient for the interaction with UVRAG.
Function
May be required for normal outer mitochondrial membrane dynamics (PubMed:15452144). Required for coatomer-mediated retrograde transport in certain cells (By similarity). May recruit other proteins to membranes with high curvature. May promote membrane fusion (PubMed:11604418). Involved in activation of caspase-dependent apoptosis by promoting BAX/BAK1 activation (PubMed:16227588). Isoform 1 acts proapoptotic in fibroblasts (By similarity). Involved in caspase-independent apoptosis during nutrition starvation and involved in the regulation of autophagy. Activates lipid kinase activity of PIK3C3 during autophagy probably by associating with the PI3K complex II (PI3KC3-C2) (PubMed:17891140). Associated with PI3KC3-C2 during autophagy may regulate the trafficking of ATG9A from the Golgi complex to the peripheral cytoplasm for the formation of autophagosomes by inducing Golgi membrane tubulation and fragmentation (PubMed:21068542). Involved in regulation of degradative endocytic trafficking and cytokinesis, probably in the context of PI3KC3-C2 (PubMed:20643123). Isoform 2 acts antiapoptotic in neuronal cells; involved in maintenance of mitochondrial morphology and promotes neuronal viability (By similarity).
Post-translational modifications
Phosphorylated at Thr-145 by CDK5; this phosphorylation is required for autophagy induction in starved neurons and facilitates homodimerization.
Sequence Similarities
Belongs to the endophilin family.
Tissue Specificity
Highly expressed in heart, skeletal muscle, kidney and placenta. Detected at lower levels in brain, colon, thymus, spleen, liver, small intestine, lung and peripheral blood leukocytes.
Cellular localization
- Cytoplasm
- Golgi apparatus membrane
- Peripheral membrane protein
- Mitochondrion outer membrane
- Peripheral membrane protein
- Cytoplasmic vesicle
- Autophagosome membrane
- Midbody
- Association with the Golgi apparatus depends on the cell type (By similarity). Following starvation colocalizes with ATG5 and LC3 autophagy-related protein(s)on autophagosomal membranes (PubMed:17891140).
Alternative names
KIAA0491, CGI-61, SH3GLB1, Endophilin-B1, Bax-interacting factor 1, SH3 domain-containing GRB2-like protein B1, Bif-1