Mitochondrial binding of hexokinase II inhibits Bax-induced cytochrome c release and apoptosis

602Citations
Citations of this article
278Readers
Mendeley users who have this article in their library.

This article is free to access.

Abstract

Proapoptotic proteins such as Bax, undergo translocation to the mitochondria during apoptosis, where they mediate the release of intermembrane space proteins including cytochrome c. Bax binds to the voltage-dependent anion channel (VDAC). VDAC is a β-barrel protein located in the outer mitochondrial membrane. In planar lipid bilayers, Bax and VDAC form a channel through which cytochrome c can pass. Hexokinase II (HXK II) also binds to VDAC. HXK II catalyzes the first step of glycolysis and is highly expressed in transformed cells, where over 70% of it is bound to the mitochondria. The present study demonstrates that HXK II interferes with the ability of Bax to bind to mitochondria and release cytochrome c. Detachment of HXK II from the mitochondria-enriched fraction isolated from HeLa cells promoted the binding of recombinant Bax-Δ19 and subsequent cytochrome c release. Similarly, the addition of recombinant HXK II to the mitochondria-enriched fraction isolated from hepatocytes, cells that do not express HXK II endogenously, prevented the ability of recombinant Bax-Δ19 to bind to the mitochondria and promote cytochrome c release. Similar results were found in intact cells, in which the detachment of mitochondrial bound HXK II or its overexpression potentiated and inhibited, respectively, Bax-induced mitochondrial dysfunction and cell death.

Cite

CITATION STYLE

APA

Pastorino, J. G., Shulga, N., & Hoek, J. B. (2002). Mitochondrial binding of hexokinase II inhibits Bax-induced cytochrome c release and apoptosis. Journal of Biological Chemistry, 277(9), 7610–7618. https://doi.org/10.1074/jbc.M109950200

Register to see more suggestions

Mendeley helps you to discover research relevant for your work.

Already have an account?

Save time finding and organizing research with Mendeley

Sign up for free