Disease relevance of Bik

• We have identified a novel cellular protein, Bik, that interacts with the cellular survival-promoting proteins, Bcl-2 and Bcl-xL, as well as the viral survival-promoting proteins, Epstein Barr virus-BHRF1 and adenovirus E1B-19 kDa [1].

High impact information on Bik

• Consistently, Bid/Bik induced apoptosis without Deltapsi loss, whereas Bax induced apoptosis with Deltapsi loss [2].
• Like Bcl-2, the biochemical mechanism of E1B 19K function includes binding to and antagonization of cellular proapoptotic proteins such as Bax, Bak, and Nbk/Bik [3].
• Bik overexpression sufficed to induce apoptosis in these cells [4].
• The proteasome inhibitor lactacystin differentially regulated the protein levels of proapoptotic Bcl-2 family members and Bik was accumulated at the mitochondria [4].
• These results show that proteasomes can modulate apoptosis of lymphocytes by affecting the half-life of Bcl-2 family members, Bik being one of them [4].

Biological context of Bik

• In transient transfection assays, Bik promotes cell death in a manner similar to the death-promoting members of the Bcl-2 family, Bax and Bak [1].

Anatomical context of Bik

• Bcl-x(L) interacted with Bik in the cells, and Bcl-x(L) overexpression prevented cytochrome c leakage out of the mitochondria, corrected the mitochondrial membrane potential defect, and protected the cells from apoptosis [4].

Associations of Bik with chemical compounds

• While Bik does not show overt homology to the BH1 and BH2 conserved domains characteristic of the Bcl-2 family, it does share a 9 amino acid domain (BH3) with Bax and Bak which may be a critical determinant for the death-promoting activity of these proteins [1].

Regulatory relationships of Bik

• This death-promoting activity of Bik can be suppressed by coexpression of Bcl-2, Bcl-XL, EBV-BHRF1 and E1B-19 kDa proteins suggesting that Bik may be a common target for both cellular and viral anti-apoptotic proteins [1].

References