Skip to main content
NCBI home page
Protein & Cell logoLink to Protein & Cell
. 2012 Oct 11;3(10):790–801. doi: 10.1007/s13238-012-2069-7

Human Bop is a novel BH3-only member of the Bcl-2 protein family

Xiaoping Zhang 1,3, Changjiang Weng 1, Yuan Li 1,3, Xiaoyan Wang 1,4, Chunsun Jiang 2, Xuemei Li 1, Youli Xu 1, Quan Chen 2, Lei Pan 1,✉, Hong Tang 1,✉
PMCID: PMC4875348  PMID: 23055042

Abstract

One group of Bcl-2 protein family, which shares only the BH3 domain (BH3-only), is critically involved in the regulation of programmed cell death. Herein we demonstrated a novel human BH3-only protein (designated as Bop) which could induce apoptosis in a BH3 domain-dependent manner. Further analysis indicated that Bop mainly localized to mitochondria and used its BH3 domain to contact the loop regions of voltage dependent anion channel 1 (VDAC1) in the outer mitochondrial membrane. In addition, purified Bop protein induced the loss of mitochondrial transmembrane potential (Δψm) and the release of cytochrome c. Furthermore, Bop used its BH3 domain to contact pro-survival Bcl-2 family members (Bcl-2, Bcl-XL, Mcl-1, A1 and Bcl-w), which could inhibit Bop-induced apoptosis. Bop would be constrained by pro-survival Bcl-2 proteins in resting cells, because Bop became released from phosphorylated Bcl-2 induced by microtubule-interfering agent like vincristine (VCR). Indeed, knockdown experiments indicated that Bop was partially required for VCR induced cell death. Finally, Bop might need to function through Bak and Bax, likely by releasing Bak from Bcl-XL sequestration. In conclusion, Bop may be a novel BH3-only factor that can engage with the regulatory network of Bcl-2 family members to process intrinsic apoptotic signaling.

Keywords: apoptosis, BH3 domain, Bop

Footnotes

These authors contributed equally to the work.

Contributor Information

Lei Pan, Email: panlei@moon.ibp.ac.cn.

Hong Tang, Email: tanghong@moon.ibp.ac.cn.

References

  1. Banerjee J., Ghosh S. Bax increases the pore size of rat brain mitochondrial voltage-dependent anion channel in the presence of tBid. Biochem Biophys Res Commun. 2004;323:310–314. doi: 10.1016/j.bbrc.2004.08.094. [DOI] [PubMed] [Google Scholar]
  2. Chen L., Willis S.N., Wei A., Smith B.J., Fletcher J.I., Hinds M.G., Colman P.M., Day C.L., Adams J.M., Huang D.C. Differential targeting of prosurvival Bcl-2 proteins by their BH3-only ligands allows complementary apoptotic function. Mol Cell. 2005;17:393–403. doi: 10.1016/j.molcel.2004.12.030. [DOI] [PubMed] [Google Scholar]
  3. Cheng E.H., Sheiko T.V., Fisher J.K., Craigen W.J., Korsmeyer S.J. VDAC2 inhibits BAK activation and mitochondrial apoptosis. Science. 2003;301:513–517. doi: 10.1126/science.1083995. [DOI] [PubMed] [Google Scholar]
  4. Cory S., Adams J.M. The Bcl2 family: regulators of the cellular life-or-death switch. Nat Rev Cancer. 2002;2:647–656. doi: 10.1038/nrc883. [DOI] [PubMed] [Google Scholar]
  5. Crompton M. The mitochondrial permeability transition pore and its role in cell death. Biochem J. 1999;341(Pt2):233–249. doi: 10.1042/bj3410233. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Crompton M., Barksby E., Johnson N., Capano M. Mitochondrial intermembrane junctional complexes and their involvement in cell death. Biochimie. 2002;84:143–152. doi: 10.1016/S0300-9084(02)01368-8. [DOI] [PubMed] [Google Scholar]
  7. Danial N.N., Korsmeyer S.J. Cell death: critical control points. Cell. 2004;116:205–219. doi: 10.1016/S0092-8674(04)00046-7. [DOI] [PubMed] [Google Scholar]
  8. Giam M., Huang D.C., Bouillet P. BH3-only proteins and their roles in programmed cell death. Oncogene. 2008;27(Suppl1):S128–136. doi: 10.1038/onc.2009.50. [DOI] [PubMed] [Google Scholar]
  9. Haldar S., Jena N., Croce C.M. Inactivation of Bcl-2 by phosphorylation. Proc Natl Acad Sci U S A. 1995;92:4507–4511. doi: 10.1073/pnas.92.10.4507. [DOI] [PMC free article] [PubMed] [Google Scholar]
  10. Happo L., Strasser A., Cory S. BH3-only proteins in apoptosis at a glance. J Cell Sci. 2012;125:1081–1087. doi: 10.1242/jcs.090514. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Hinds M.G., Day C.L. Regulation of apoptosis: uncovering the binding determinants. Curr Opin Struct Biol. 2005;15:690–699. doi: 10.1016/j.sbi.2005.10.003. [DOI] [PubMed] [Google Scholar]
  12. Huang D.C., Strasser A. BH3-Only proteins-essential initiators of apoptotic cell death. Cell. 2000;103:839–842. doi: 10.1016/S0092-8674(00)00187-2. [DOI] [PubMed] [Google Scholar]
  13. Jiang X., Wang X. Cytochrome C-mediated apoptosis. Annu Rev Biochem. 2004;73:87–106. doi: 10.1146/annurev.biochem.73.011303.073706. [DOI] [PubMed] [Google Scholar]
  14. Jones D.T. Protein secondary structure prediction based on position-specific scoring matrices. J Mol Biol. 1999;292:195–202. doi: 10.1006/jmbi.1999.3091. [DOI] [PubMed] [Google Scholar]
  15. Kelekar A., Thompson C.B. Bcl-2-family proteins: the role of the BH3 domain in apoptosis. Trends Cell Biol. 1998;8:324–330. doi: 10.1016/S0962-8924(98)01321-X. [DOI] [PubMed] [Google Scholar]
  16. Kim H., Rafiuddin-Shah M., Tu H.C., Jeffers J.R., Zambetti G.P., Hsieh J.J., Cheng E.H. Hierarchical regulation of mitochondrion-dependent apoptosis by BCL-2 subfamilies. Nat Cell Biol. 2006;8:1348–1358. doi: 10.1038/ncb1499. [DOI] [PubMed] [Google Scholar]
  17. Kuwana T., Bouchier-Hayes L., Chipuk J.E., Bonzon C., Sullivan B.A., Green D.R., Newmeyer D.D. BH3 domains of BH3-only proteins differentially regulate Bax-mediated mitochondrial membrane permeabilization both directly and indirectly. Mol Cell. 2005;17:525–535. doi: 10.1016/j.molcel.2005.02.003. [DOI] [PubMed] [Google Scholar]
  18. Leber B., Geng F., Kale J., Andrews D.W. Drugs targeting Bcl-2 family members as an emerging strategy in cancer. Expert Rev Mol Med. 2010;12:e28. doi: 10.1017/S1462399410001572. [DOI] [PubMed] [Google Scholar]
  19. Letai A., Bassik M.C., Walensky L.D., Sorcinelli M.D., Weiler S., Korsmeyer S.J. Distinct BH3 domains either sensitize or activate mitochondrial apoptosis, serving as prototype cancer therapeutics. Cancer Cell. 2002;2:183–192. doi: 10.1016/S1535-6108(02)00127-7. [DOI] [PubMed] [Google Scholar]
  20. Liu Y., Yang Y., Ye Y.C., Shi Q.F., Chai K., Tashiro S., Onodera S., Ikejima T. Activation of ERK-p53 and ERK-mediated phosphorylation of Bcl-2 are involved in autophagic cell death induced by the c-Met inhibitor SU11274 in human lung cancer A549 cells. J Pharmacol Sci. 2012;118:423–432. doi: 10.1254/jphs.11181FP. [DOI] [PubMed] [Google Scholar]
  21. Lomonosova E., Chinnadurai G. BH3-only proteins in apoptosis and beyond: an overview. Oncogene. 2008;27(Suppl1):S2–19. doi: 10.1038/onc.2009.39. [DOI] [PMC free article] [PubMed] [Google Scholar]
  22. Moldoveanu T., Liu Q., Tocilj A., Watson M., Shore G., Gehring K. The X-ray structure of a BAK homodimer reveals an inhibitory zinc binding site. Mol Cell. 2006;24:677–688. doi: 10.1016/j.molcel.2006.10.014. [DOI] [PubMed] [Google Scholar]
  23. Petros A.M., Olejniczak E.T., Fesik S.W. Structural biology of the Bcl-2 family of proteins. Biochim Biophys Acta. 2004;1644:83–94. doi: 10.1016/j.bbamcr.2003.08.012. [DOI] [PubMed] [Google Scholar]
  24. Poommipanit P.B., Chen B., Oltvai Z.N. Interleukin-3 induces the phosphorylation of a distinct fraction of bcl-2. J Biol Chem. 1999;274:1033–1039. doi: 10.1074/jbc.274.2.1033. [DOI] [PubMed] [Google Scholar]
  25. Shamas-Din A., Brahmbhatt H., Leber B., Andrews D.W. BH3-only proteins: Orchestrators of apoptosis. Biochim Biophys Acta. 2011;1813:508–520. doi: 10.1016/j.bbamcr.2010.11.024. [DOI] [PubMed] [Google Scholar]
  26. Shi Y., Chen J., Weng C., Chen R., Zheng Y., Chen Q., Tang H. Identification of the protein-protein contact site and interaction mode of human VDAC1 with Bcl-2 family proteins. Biochem Biophys Res Commun. 2003;305:989–996. doi: 10.1016/S0006-291X(03)00871-4. [DOI] [PubMed] [Google Scholar]
  27. Shimizu S., Ide T., Yanagida T., Tsujimoto Y. Electrophysiological study of a novel large pore formed by Bax and the voltage-dependent anion channel that is permeable to cytochrome c. J Biol Chem. 2000;275:12321–12325. doi: 10.1074/jbc.275.16.12321. [DOI] [PubMed] [Google Scholar]
  28. Shimizu S., Matsuoka Y., Shinohara Y., Yoneda Y., Tsujimoto Y. Essential role of voltage-dependent anion channel in various forms of apoptosis in mammalian cells. J Cell Biol. 2001;152:237–250. doi: 10.1083/jcb.152.2.237. [DOI] [PMC free article] [PubMed] [Google Scholar]
  29. Shimizu S., Narita M., Tsujimoto Y. Bcl-2 family proteins regulate the release of apoptogenic cytochrome c by the mitochondrial channel VDAC. Nature. 1999;399:483–487. doi: 10.1038/20959. [DOI] [PubMed] [Google Scholar]
  30. Srivastava R.K., Srivastava A.R., Korsmeyer S.J., Nesterova M., Cho-Chung Y.S., Longo D.L. Involvement of microtubules in the regulation of Bcl2 phosphorylation and apoptosis through cyclic AMP-dependent protein kinase. Mol Cell Biol. 1998;18:3509–3517. doi: 10.1128/MCB.18.6.3509. [DOI] [PMC free article] [PubMed] [Google Scholar]
  31. Strausberg R.L., Feingold E.A., Grouse L.H., Derge J.G., Klausner R.D., Collins F.S., Wagner L., Shenmen C.M., Schuler G.D., Altschul S.F., et al. Generation and initial analysis of more than 15,000 full-length human and mouse cDNA sequences. Proc Natl Acad Sci U S A. 2002;99:16899–16903. doi: 10.1073/pnas.242603899. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Sugiyama T., Shimizu S., Matsuoka Y., Yoneda Y., Tsujimoto Y. Activation of mitochondrial voltage-dependent anion channel by apro-apoptotic BH3-only protein Bim. Oncogene. 2002;21:4944–4956. doi: 10.1038/sj.onc.1205621. [DOI] [PubMed] [Google Scholar]
  33. Suzuki M., Youle R.J., Tjandra N. Structure of Bax: coregulation of dimer formation and intracellular localization. Cell. 2000;103:645–654. doi: 10.1016/S0092-8674(00)00167-7. [DOI] [PubMed] [Google Scholar]
  34. Taylor J.W., Ott J., Eckstein F. The rapid generation of oligonucleotide-directed mutations at high frequency using phosphorothioate-modified DNA. Nucleic Acids Res. 1985;13:8765–8785. doi: 10.1093/nar/13.24.8765. [DOI] [PMC free article] [PubMed] [Google Scholar]
  35. Tsujimoto Y., Shimizu S. The voltage-dependent anion channel: an essential player in apoptosis. Biochimie. 2002;84:187–193. doi: 10.1016/S0300-9084(02)01370-6. [DOI] [PubMed] [Google Scholar]
  36. van Delft M.F., Huang D.C. How the Bcl-2 family of proteins interact to regulate apoptosis. Cell Res. 2006;16:203–213. doi: 10.1038/sj.cr.7310028. [DOI] [PubMed] [Google Scholar]
  37. Vo T.T., Letai A. BH3-only proteins and their effects on cancer. Adv Exp Med Biol. 2010;687:49–63. doi: 10.1007/978-1-4419-6706-0_3. [DOI] [PMC free article] [PubMed] [Google Scholar]
  38. Weng C., Li Y., Xu D., Shi Y., Tang H. Specific cleavage of Mcl-1 by caspase-3 in tumor necrosis factor-related apoptosis-inducing ligand (TRAIL)-induced apoptosis in Jurkat leukemia T cells. J Biol Chem. 2005;280:10491–10500. doi: 10.1074/jbc.M412819200. [DOI] [PubMed] [Google Scholar]
  39. Willis S.N., Adams J.M. Life in the balance: how BH3-only proteins induce apoptosis. Curr Opin Cell Biol. 2005;17:617–625. doi: 10.1016/j.ceb.2005.10.001. [DOI] [PMC free article] [PubMed] [Google Scholar]
  40. Willis S.N., Chen L., Dewson G., Wei A., Naik E., Fletcher J.I., Adams J.M., Huang D.C. Proapoptotic Bak is sequestered by Mcl-1 and Bcl-xL, but not Bcl-2, until displaced by BH3-only proteins. Genes Dev. 2005;19:1294–1305. doi: 10.1101/gad.1304105. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Wong W.W., Puthalakath H. Bcl-2 family proteins: the sentinels of the mitochondrial apoptosis pathway. IUBMB Life. 2008;60:390–397. doi: 10.1002/iub.51. [DOI] [PubMed] [Google Scholar]
  42. Yamamoto K., Ichijo H., Korsmeyer S.J. BCL-2 is phosphorylated and inactivated by an ASK1/Jun N-terminal protein kinase pathway normally activated at G(2)/M. Mol Cell Biol. 1999;19:8469–8478. doi: 10.1128/MCB.19.12.8469. [DOI] [PMC free article] [PubMed] [Google Scholar]
  43. Zheng Y., Shi Y., Tian C., Jiang C., Jin H., Chen J., Almasan A., Tang H., Chen Q. Essential role of the voltage-dependent anion channel (VDAC) in mitochondrial permeability transition pore opening and cytochrome c release induced by arsenic trioxide. Oncogene. 2004;23:1239–1247. doi: 10.1038/sj.onc.1207205. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Zong W.X., Lindsten T., Ross A.J., MacGregor G.R., Thompson C.B. BH3-only proteins that bind pro-survival Bcl-2 family members fail to induce apoptosis in the absence of Bax and Bak. Genes Dev. 2001;15:1481–1486. doi: 10.1101/gad.897601. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Protein & Cell are provided here courtesy of Oxford University Press

RESOURCES