Endophilin-B1 is a

protein Proteins are large biomolecules and macromolecules that comprise one or more long chains of amino acid residues. Proteins perform a vast array of functions within organisms, including catalysing metabolic reactions, DNA replication, res ...

that in humans is encoded by the ''SH3GLB1''

gene In biology, the word gene (from , ; "... Wilhelm Johannsen coined the word gene to describe the Mendelian units of heredity..." meaning ''generation'' or ''birth'' or ''gender'') can have several different meanings. The Mendelian gene is a b ...

. Endophilin-B1 belongs to the Bin/Amphiphysin/Rvs167 (

BAR Bar or BAR may refer to: Food and drink * Bar (establishment), selling alcoholic beverages * Candy bar * Chocolate bar Science and technology * Bar (river morphology), a deposit of sediment * Bar (tropical cyclone), a layer of cloud * Bar (u ...

) family of proteins and plays a critical role in mitochondrial fission and

fusion Fusion, or synthesis, is the process of combining two or more distinct entities into a new whole. Fusion may also refer to: Science and technology Physics *Nuclear fusion, multiple atomic nuclei combining to form one or more different atomic nucl ...

, as well as in autophagy and apoptosis. Loss of functional endophilin-B1 is seen in many different forms of

cancer Cancer is a group of diseases involving abnormal cell growth with the potential to invade or spread to other parts of the body. These contrast with benign tumors, which do not spread. Possible signs and symptoms include a lump, abnormal b ...

. The link between carcinogenesis and dysregulation of cell death pathways suggests that endophilin-B1 serves a critical tumor suppressor role in the cell, although the underlying mechanisms are not known.

Structure

In the presence of model

biological membranes A biological membrane, biomembrane or cell membrane is a selectively permeable membrane that separates the interior of a cell from the external environment or creates intracellular compartments by serving as a boundary between one part of the c ...

, endophilin-B1 dimers assemble into helical scaffolds around the membrane and drive its tubulation.

Interactions

In addition to the membrane binding and remodeling properties endophilin-B1 shares with many other BAR proteins, endophilin-B1 interacts with the pro-apoptotic factor

Bcl-2-associated X protein Apoptosis regulator BAX, also known as bcl-2-like protein 4, is a protein that in humans is encoded by the ''BAX'' gene. ''BAX'' is a member of the Bcl-2 gene family. BCL2 family members form hetero- or homodimers and act as anti- or pro-apopto ...

(Bax) and

SH3GLB2 Endophilin-B2 is a protein that in humans is encoded by the ''SH3GLB2'' gene. Interactions SH3GLB2 has been shown to interact with SH3GLB1 and SH3KBP1 SH3 domain-containing kinase-binding protein 1 (synonyms - CIN85, in rodents - Ruk) is an ...

. It has also been shown to interact with a wide variety of proteins through a canonical

SH3 domain The SRC Homology 3 Domain (or SH3 domain) is a small protein domain of about 60 amino acid residues. Initially, SH3 was described as a conserved sequence in the viral adaptor protein v-Crk. This domain is also present in the molecules of phos ...

that enables PxxP motif-containing protein interactions, including Beclin-1,

amphiphysin Amphiphysin is a protein that in humans is encoded by the ''AMPH'' gene. Function This gene encodes a protein associated with the cytoplasmic surface of synaptic vesicles. A subset of patients with stiff person syndrome who were also affected ...

-1, amphiphysin-2, and

huntingtin Huntingtin (Htt) is the protein coded for in humans by the ''HTT'' gene, also known as the ''IT15'' ("interesting transcript 15") gene. Mutated ''HTT'' is the cause of Huntington's disease (HD), and has been investigated for this role and also fo ...

Structure

Interactions

References

Further reading