Bcl-2 homologous antagonist/killer is a protein

Protein

Proteins are biochemical compounds consisting of one or more polypeptides typically folded into a globular or fibrous form, facilitating a biological function. A polypeptide is a single linear polymer chain of amino acids bonded together by peptide bonds between the carboxyl and amino groups of...

 that in humans is encoded by the BAK1 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

. BAK1 orthologs  have been identified in most mammals for which complete genome data are available.

The BAK protein is a pro-apoptotic

Apoptosis

Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...

 member of the Bcl-2

Bcl-2

Bcl-2 is the founding member of the Bcl-2 family of apoptosis regulator proteins encoded by the BCL2 gene. Bcl-2 derives its name from B-cell lymphoma 2, as it is the second member of a range of proteins initially described in chromosomal translocations involving chromosomes 14 and 18 in...

 gene family

Gene family

A gene family is a set of several similar genes, formed by duplication of a single original gene, and generally with similar biochemical functions...

 which is involved in initiating apoptosis

Apoptosis

Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...

. Dysregulation of the BAK gene has been implicated in human gastrointestinal cancers, indicating that the gene plays a part in the pathogenesis

Pathogenesis

The pathogenesis of a disease is the mechanism by which the disease is caused. The term can also be used to describe the origin and development of the disease and whether it is acute, chronic or recurrent...

 of some cancers.

Function

The protein encoded by this gene belongs to the BCL2 protein family. BCL2 family members form oligomers or heterodimers and act as anti- or pro-apoptotic regulators that are involved in a wide variety of cellular activities. This protein localizes to mitochondria, and functions to induce apoptosis

Apoptosis

Apoptosis is the process of programmed cell death that may occur in multicellular organisms. Biochemical events lead to characteristic cell changes and death. These changes include blebbing, cell shrinkage, nuclear fragmentation, chromatin condensation, and chromosomal DNA fragmentation...

. It interacts with and accelerates the opening of the mitochondrial voltage-dependent anion channel, which leads to a loss in membrane potential and the release of cytochrome c

Cytochrome c

The Cytochrome complex, or cyt c is a small heme protein found loosely associated with the inner membrane of the mitochondrion. It belongs to the cytochrome c family of proteins. Cytochrome c is a highly soluble protein, unlike other cytochromes, with a solubility of about 100 g/L and is an...

. This protein also interacts with the tumor suppressor P53 after exposure to cell stress.

BAK1 gene variation

Recently, one study of the role of genetics in abdominal aortic aneurism (AAA) showed that different BAK1 variants can exist in both diseased and nondiseased AA tissues compared to matching blood samples. Since its publication, this observation has raised many discussions among scientific community because it seems to jeopardize the current paradigm that all cells have the same genomic DNA.
However, BAK1 gene variants in different tissues may be easily explained by the expression of BAK1 gene on chromosome 6 and one its edited copies on chromosome 20. This conjecture reconciles both the current paradigm and the observation of BAK1 gene variation in different tissues. However, the authors of the BAK1 gene variations original article have published a response.

Interactions

BAK1 has been shown to interact

Protein-protein interaction

Protein–protein interactions occur when two or more proteins bind together, often to carry out their biological function. Many of the most important molecular processes in the cell such as DNA replication are carried out by large molecular machines that are built from a large number of protein...

 with BCL2-like 1

BCL2-like 1 (gene)

Bcl-2-like protein 1 is a protein that in humans is encoded by the BCL2L1 gene.-Interactions:BCL2-like 1 has been shown to interact with RAD9A, RTN1, BAK1, Reticulon 4, Bcl-2-associated X protein, BCAP31, Bcl-2-interacting killer, PPP1CA, Noxa, VDAC1, BCL2L11, Bcl-2-associated death promoter,...

, Bcl-2

Bcl-2

Bcl-2 is the founding member of the Bcl-2 family of apoptosis regulator proteins encoded by the BCL2 gene. Bcl-2 derives its name from B-cell lymphoma 2, as it is the second member of a range of proteins initially described in chromosomal translocations involving chromosomes 14 and 18 in...

, P53

P53

p53 , is a tumor suppressor protein that in humans is encoded by the TP53 gene. p53 is crucial in multicellular organisms, where it regulates the cell cycle and, thus, functions as a tumor suppressor that is involved in preventing cancer...

 and MCL1

MCL1

Induced myeloid leukemia cell differentiation protein Mcl-1 is a protein that in humans is encoded by the MCL1 gene.- Function :The protein encoded by this gene belongs to the Bcl-2 family. Alternative splicing occurs at this locus and two transcript variants encoding distinct isoforms have been...

.

Further reading