Domain

Apoptosis, Bim N-terminal (IPR014771)

Short name: Apoptosis_Bim_N

Domain relationships

None.

Description

Apoptosis, or programmed cell death (PCD), is a common and evolutionarily conserved property of all metazoans [PMID: 11341280]. In many biological processes, apoptosis is required to eliminate supernumerary or dangerous (such as pre-cancerous) cells and to promote normal development. Dysregulation of apoptosis can, therefore, contribute to the development of many major diseases including cancer, autoimmunity and neurodegenerative disorders. In most cases, proteins of the caspase family execute the genetic programme that leads to cell death.

Bcl-2 proteins are central regulators of caspase activation, and play a key role in cell death by regulating the integrity of the mitochondrial and endoplasmic reticulum (ER) membranes [PMID: 12631689]. At least 20 Bcl-2 proteins have been reported in mammals, and several others have been identified in viruses. Bcl-2 family proteins fall roughly into three subtypes, which either promote cell survival (anti-apoptotic) or trigger cell death (pro-apoptotic). All members contain at least one of four conserved motifs, termed Bcl-2 Homology (BH) domains. Bcl-2 subfamily proteins, which contain at least BH1 and BH2, promote cell survival by inhibiting the adapters needed for the activation of caspases.

Pro-apoptotic members potentially exert their effects by displacing the adapters from the pro-survival proteins; these proteins belong either to the Bax subfamily, which contain BH1-BH3, or to the BH3 subfamily, which mostly only feature BH3 [PMID: 9735050]. Thus, the balance between antagonistic family members is believed to play a role in determining cell fate. Members of the wider Bcl-2 family, which also includes Bcl-x, Bcl-w and Mcl-1, are described by their similarity to Bcl-2 protein, a member of the pro-survival Bcl-2 subfamily [PMID: 9735050]. Full-length Bcl-2 proteins feature all four BH domains, seven alpha-helices, and a C-terminal hydrophobic motif that targets the protein to the outer mitochondrial membrane, ER and nuclear envelope.

This entry represents the N-terminal region of several mammal specific Bim proteins. The Bim protein is one of the BH3-only proteins, members of the Bcl-2 family that have only one of the Bcl-2 homology regions, BH3.

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.
Pfam