Characterization of an alternative BAK-binding site for BH3 peptides

Kaiqin Ye; Wei X Meng; Hongbin Sun; Bo Wu; Meng Chen; Yuan-Ping Pang; Jia Gao; Hongzhi Wang; Junfeng Wang; Scott H Kaufmann; Haiming Dai

doi:10.1038/s41467-020-17074-y

Characterization of an alternative BAK-binding site for BH3 peptides

Nat Commun. 2020 Jul 3;11(1):3301. doi: 10.1038/s41467-020-17074-y.

Authors

Kaiqin Ye^{1

2}, Wei X Meng^{3

4}, Hongbin Sun⁵, Bo Wu⁶, Meng Chen^{1

2}, Yuan-Ping Pang⁴, Jia Gao^{1

2}, Hongzhi Wang^{1

2}, Junfeng Wang⁶, Scott H Kaufmann^{7

8}, Haiming Dai^{9

10}

Affiliations

¹ Anhui Province Key Laboratory of Medical Physics and Technology, Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China.
² Hefei Cancer Hospital, Chinese Academy of Sciences, Hefei, 230031, China.
³ Division of Oncology Research, Mayo Clinic, Rochester, MN, USA.
⁴ Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA.
⁵ School of Food and Biological Engineering, Zhenzhou University of Light Industry, Zhenzhou, 450002, China.
⁶ CAS Key Laboratory of High Magnetic Field and Ion Beam Physical Biology, High Magnetic Field Laboratory, HFIPS, Chinese Academy of Sciences, Hefei, 230031, China.
⁷ Division of Oncology Research, Mayo Clinic, Rochester, MN, USA. Kaufmann.Scott@mayo.edu.
⁸ Department of Molecular Pharmacology and Experimental Therapeutics, Mayo Clinic, Rochester, MN, 55905, USA. Kaufmann.Scott@mayo.edu.
⁹ Anhui Province Key Laboratory of Medical Physics and Technology, Center of Medical Physics and Technology, Hefei Institutes of Physical Science, Chinese Academy of Sciences, Hefei, 230031, China. daih@cmpt.ac.cn.
¹⁰ Hefei Cancer Hospital, Chinese Academy of Sciences, Hefei, 230031, China. daih@cmpt.ac.cn.

Abstract

Many cellular stresses are transduced into apoptotic signals through modification or up-regulation of the BH3-only subfamily of BCL2 proteins. Through direct or indirect mechanisms, these proteins activate BAK and BAX to permeabilize the mitochondrial outer membrane. While the BH3-only proteins BIM, PUMA, and tBID have been confirmed to directly activate BAK through its canonical BH3 binding groove, whether the BH3-only proteins BMF, HRK or BIK can directly activate BAK is less clear. Here we show that BMF and HRK bind and directly activate BAK. Through NMR studies, site-directed mutagenesis, and advanced molecular dynamics simulations, we also find that BAK activation by BMF and possibly HRK involves a previously unrecognized binding groove formed by BAK α4, α6, and α7 helices. Alterations in this groove decrease the ability of BMF and HRK to bind BAK, permeabilize membranes and induce apoptosis, suggesting a potential role for this BH3-binding site in BAK activation.

Publication types

Research Support, Non-U.S. Gov't

MeSH terms

Adaptor Proteins, Signal Transducing / chemistry
Adaptor Proteins, Signal Transducing / genetics
Adaptor Proteins, Signal Transducing / metabolism*
Amino Acid Sequence
Animals
Apoptosis Regulatory Proteins / chemistry
Apoptosis Regulatory Proteins / genetics
Apoptosis Regulatory Proteins / metabolism*
Binding Sites / genetics
Cells, Cultured
Humans
Jurkat Cells
Magnetic Resonance Spectroscopy
Mice, Knockout
Mitochondrial Membranes / metabolism
Molecular Dynamics Simulation
Mutation
Protein Binding
Protein Domains
Proto-Oncogene Proteins c-bcl-2 / chemistry
Proto-Oncogene Proteins c-bcl-2 / genetics
Proto-Oncogene Proteins c-bcl-2 / metabolism
Sequence Homology, Amino Acid
bcl-2 Homologous Antagonist-Killer Protein / chemistry
bcl-2 Homologous Antagonist-Killer Protein / genetics
bcl-2 Homologous Antagonist-Killer Protein / metabolism*

Substances

Adaptor Proteins, Signal Transducing
Apoptosis Regulatory Proteins
BCL2 protein, human
BMF protein, human
HRK protein, human
Proto-Oncogene Proteins c-bcl-2
bcl-2 Homologous Antagonist-Killer Protein