About BID / BH3 Interacting Domain Death Agonist:
Defined as a protein-coding gene, BH3 Interacting Domain Death Agonist (BID) is a member of the Bcl-2 protein family. It is pro-apoptotic, meaning that it facilitates cell death or mutation via its impact on various cellular activities.
BID Function
BH3 Interacting Domain Death Agonist counteracts the protective effect of Bcl-2 and induces apoptosis and caspases. The main protease present in BH3 Interacting Domain Death Agonist in p15 BID, which facilitates the release of cytochrome c. Isoform 1, 2, and 4 induce ICE-like proteases and apoptosis, whereas Isoform 3 does not.
BH3 Interacting Domain Death Agonist Interactions
BH3 Interacting Domain Death Agonist interacts with BAX, another member of the Bcl-2 protein family, as well as Serine/threonine-protein kinase ATR, Caspase 2, Caspase-8, Induced myeloid leukemia cell differentiation protein Mcl-1, and Replication protein A (RPA).
BID Mechanism
Upon interaction, BH3 Interacting Domain Death Agonist infiltrates a cell and typically instigates modification or cell death. When BID interacts with BAX, for example, BAX is inserted into the organelle membranes. Subsequently, the mitochondria release cytochrome c, in addition to other pro-apoptotic factors, which, in turn, activates caspases.
If tumor suppressor p53 is present, the expression of BH3 Interacting Domain Death Agonist is upregulated. Due to this, BID is also believed to be involved in p53-mediated apoptosis.
Additionally, studies have shown that BID is often activated in response to particular apoptotic stimuli in a death receptor-independent manner.
However, Bcl-2 and anti-apoptotic proteins within the Bcl-2 family, are capable of inhibiting BID’s ability to activate BAX. As a result, anti-apoptotic Bcl-2 proteins can minimize the impact of BID by binding to BAX.