The BAX gene (BAX stands for: BCL2 Associated X, Apoptosis Regulator) is a protein coding gene located on chromosome 19q13.33. Several alternatively spliced transcript variants encoding different isoforms are known for this gene.
BAX gene
DefinitionThis section has been translated automatically.
General informationThis section has been translated automatically.
The protein encoded by the BAX gene belongs to the BCL2 protein family. Members of the BCL2 family form hetero- or homodimers and act as anti- or pro-apoptotic regulators involved in a variety of cellular activities.
DAs BAX protein forms a heterodimer with BCL2 and acts as an apoptotic activator. The association and ratio of BAX to BCL2 also determine cell survival or death following an apoptotic stimulus. This protein is reported to interact with the mitochondrial voltage-dependent anion channel (VDAC) and enhance its opening, leading to loss of membrane potential and release of cytochrome C . Expression of this gene is regulated by the tumor suppressor P53 and has been shown to be involved in P53-mediated apoptosis.
PathophysiologyThis section has been translated automatically.
BAX plays a role in the mitochondrial apoptotic process (Schmitt E et al. 2000). Under normal conditions, BAX resides largely in the cytosol, through constant retrotranslocation from mitochondria to the cytosol mediated by BCL2L1/Bcl-xL, preventing accumulation of toxic BAX levels at the outer mitochondrial membrane (Edlich F et al. 2011). Under stress conditions, BAX undergoes a conformational change that causes translocation to the mitochondrial membrane and leads to the release of cytochrome C, inducing apoptosis (Tan KO et al. 2001). BAX promotes activation of CASP3 and thus apoptosis (Wei B et al. 2015).
Clinical pictureThis section has been translated automatically.
Diseases associated with BAX include:
- Colorectal carcinoma
- T-cell acute lymphoblastic leukemia.
LiteratureThis section has been translated automatically.
- Edlich F et al. (2011) Bcl-x(L) retrotranslocates Bax from the mitochondria into the cytosol. Cell 145:104-116.
- Schmitt E et al. (2000) Characterization of Bax-sigma, a cell death-inducing isoform of Bax. Biochem Biophys Res Commun 270:868-879.
- Tan KO et al (2001) MAP-1, a novel proapoptotic protein containing a BH3-like motif that associates with Bax through its Bcl-2 homology domains. J Biol Chem 276:2802-2807.
- Wei B et al. (2015) Tom70 mediates Sendai virus-induced apoptosis on mitochondria. J Virol 89:3804-3818.