Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UNIPROT:P10415 (Bcl-2)
 33,771 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

Bcl-2 family members bearing only the BH3 domain are essential inducers of apoptosis. We identified a BH3-only protein, Bmf, and show that its BH3 domain is required both for binding to prosurvival Bcl-2 proteins and for triggering apoptosis. In healthy cells, Bmf is sequestered to myosin V motors by association with dynein light chain 2. Certain damage signals, such as loss of cell attachment (anoikis), unleash Bmf, allowing it to translocate and bind prosurvival Bcl-2 proteins. Thus, at least two mammalian BH3-only proteins, Bmf and Bim, function to sense intracellular damage by their localization to distinct cytoskeletal structures.
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PMID:Bmf: a proapoptotic BH3-only protein regulated by interaction with the myosin V actin motor complex, activated by anoikis. 1154 62

Bmf is a BH3-only Bcl-2 family member that is normally sequestered to myosin V motors by binding to the dynein light chain 2 (DLC2). Certain damage signals release Bmf, which then binds prosurvival Bcl-2 proteins and triggers apoptosis. Here, two novel isoforms of human Bmf, Bmf-II and Bmf-III, were identified and cloned from cDNA derived from B-chronic lymphocytic leukemia (B-CLL) cells. Bmf-II and Bmf-III were characterized as two splice variants, lacking the BH3 domain but retaining the DLC2 binding domain. Bmf (here called Bmf-I) expression in HeLa cells induced apoptosis and reduced colony formation in contrast to Bmf-II and Bmf-III, which had no effect on apoptosis and instead increased colony formation. While bmf-I mRNA was expressed in many cell types, expression was higher in B lymphoid cells and bmf-II and bmf-III were mainly detected in B-CLL and normal B cells. bmf-I mRNA was upregulated in normal and leukemic B cells, while bmf-III mRNA was downregulated only in B-CLL cells by serum deprivation. We show that Bmf is regulated by transcriptional activation and alternative splicing and conclude that the relative levels of Bmf isoforms may have a role in regulating growth and survival in B cells and leukemic B-CLL cells.
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PMID:Expression and transcriptional regulation of functionally distinct Bmf isoforms in B-chronic lymphocytic leukemia cells. 1457 34

Bmf is a proapoptotic member of the BH3-only subgroup of Bcl-2 family proteins, which is associated to myosin V motors by binding to the dynein light chain 2 (DLC2). It acts as a sentinel detecting intracellular damages on the main cytoskeletal structures. The cloning and characterization of the chicken (Gallus gallus) Bmf cDNA and splicing variant is described in this report. The Bmf cDNA was amplified by reverse transcriptase-polymerase chain reaction (RT-PCR) using oligonucleotide primers derived from in silico sequences. The chicken Bmf cDNA encodes a protein of 193 amino acids, showing homology to mammalian Bmf proteins. A splicing variant of the chicken Bmf (Bmf(S), short isoform of Bmf) coding a protein of 118 amino acids was also identified. This is the first Bmf isoform identified so far which lacks the DLC2-binding domain although retaining the BH3 domain. Both chicken Bmf isoforms induced apoptosis 24 h after transfection in MCF7 and HeLa cell lines, but chicken Bmf(S) exhibits a higher proapoptotic activity. In addition, mRNA expression analysis showed that chicken Bmf transcription is ubiquitous in all embryo developmental stages, suggesting a role for this protein in the control of the development process.
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PMID:Characterization of the BH3 protein Bmf in Gallus gallus: identification of a novel chicken-specific isoform. 1796 19

Constitutive activation of the mitogen-activated protein kinase (MAPK) pathway is implicated in the development and progression of many human cancers, including melanoma. Mutually exclusive activating mutations in NRAS or BRAF have been identified in approximately 85% of melanomas, and components of this pathway have been developed as molecular targets for therapeutic intervention. We and others have shown that inhibition of this pathway with specific small molecule MAPK/extracellular signal-regulated kinase kinase (MEK) inhibitors induces a wide range of apoptotic responsiveness in human melanoma cells both in vitro and in vivo. To define the molecular mechanism underlying variable apoptotic sensitivity of melanoma cells to MEK inhibition, we examined the expression and subcellular localization of Bcl-2 family members in a comprehensive set of human melanoma cell lines. Whereas the proapoptotic protein Bim was activated and localized to the mitochondrial membrane in all cell lines regardless of apoptotic sensitivity, Bmf activation and cytosolic translocation was exclusive to sensitive cells. In resistant cells, Bmf remained sequestered to the cytoskeleton through dynein light chain 2 (DLC2) binding. Overexpression of Bmf in resistant cells did not enhance apoptosis, whereas expression of mutant BmfA69P, which has decreased binding to DLC2, promoted cell death. Expression of BmfA69P mutants possessing the Bcl-2 homology 3 (BH3) domain mutation L138A, which impairs BH3 interactions, did not enhance apoptosis in resistant cells. RNA interference targeting Bim and Bmf provided protection from apoptosis induced by MEK inhibition. These results show a novel role for Bmf in promoting apoptosis and provide insight into the mechanism of apoptotic resistance to MEK inhibition in melanoma.
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PMID:Mitogen-activated protein kinase inhibition induces translocation of Bmf to promote apoptosis in melanoma. 1924 5