Download MendeleyAtomic structure of the apoptosome: mechanism of cytochrome c- and dATP-mediated activation of Apaf-1
Zhou, M., Li, Y., Hu, Q., Bai, X.C., Huang, W., Yan, C., Scheres, S.H.W., Shi, Y.(2015) Genes Dev 29: 2349-2361
- PubMed: 26543158
- DOI: https://doi.org/10.1101/gad.272278.115
- Primary Citation of Related Structures:
3JBT - PubMed Abstract:
The apoptotic protease-activating factor 1 (Apaf-1) controls the onset of many known forms of intrinsic apoptosis in mammals. Apaf-1 exists in normal cells as an autoinhibited monomer. Upon binding to cytochrome c and dATP, Apaf-1 oligomerizes into a heptameric complex known as the apoptosome, which recruits and activates cell-killing caspases. Here we present an atomic structure of an intact mammalian apoptosome at 3.8 Å resolution, determined by single-particle, cryo-electron microscopy (cryo-EM). Structural analysis, together with structure-guided biochemical characterization, uncovered how cytochrome c releases the autoinhibition of Apaf-1 through specific interactions with the WD40 repeats. Structural comparison with autoinhibited Apaf-1 revealed how dATP binding triggers a set of conformational changes that results in the formation of the apoptosome. Together, these results constitute the molecular mechanism of cytochrome c- and dATP-mediated activation of Apaf-1.
Organizational Affiliation:
Ministry of Education Protein Science Laboratory, Center for Structural Biology, Tsinghua-Peking Center for Life Sciences, School of Life Sciences, School of Medicine, Tsinghua University, Beijing 100084, China;
