Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function

Cobra venom cardiotoxins (CVCs) can translocate to mitochondria to promote apoptosis by eliciting mitochondrial dysfunction. However, the molecular mechanism(s) by which CVCs are selectively targeted to the mitochondrion to disrupt mitochondrial function remains to be elucidated. By studying cardiot...

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Main Authors: Boris Zhang, Feng Li, Zhengyao Chen, Indira H. Shrivastava, Edward S. Gasanoff, Ruben K. Dagda
Format: Article
Language:English
Published: MDPI AG 2019-03-01
Series:Toxins
Subjects:
Online Access:http://www.mdpi.com/2072-6651/11/3/152
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author Boris Zhang
Feng Li
Zhengyao Chen
Indira H. Shrivastava
Edward S. Gasanoff
Ruben K. Dagda
author_facet Boris Zhang
Feng Li
Zhengyao Chen
Indira H. Shrivastava
Edward S. Gasanoff
Ruben K. Dagda
author_sort Boris Zhang
collection DOAJ
description Cobra venom cardiotoxins (CVCs) can translocate to mitochondria to promote apoptosis by eliciting mitochondrial dysfunction. However, the molecular mechanism(s) by which CVCs are selectively targeted to the mitochondrion to disrupt mitochondrial function remains to be elucidated. By studying cardiotoxin from Naja mossambica mossambica cobra (cardiotoxin VII4), a basic three-fingered S-type cardiotoxin, we hypothesized that cardiotoxin VII4 binds to cardiolipin (CL) in mitochondria to alter mitochondrial structure/function and promote neurotoxicity. By performing confocal analysis, we observed that red-fluorescently tagged cardiotoxin rapidly translocates to mitochondria in mouse primary cortical neurons and in human SH-SY5Y neuroblastoma cells to promote aberrant mitochondrial fragmentation, a decline in oxidative phosphorylation, and decreased energy production. In addition, by employing electron paramagnetic resonance (EPR) and protein nuclear magnetic resonance (1H-NMR) spectroscopy and phosphorescence quenching of erythrosine in model membranes, our compiled biophysical data show that cardiotoxin VII4 binds to anionic CL, but not to zwitterionic phosphatidylcholine (PC), to increase the permeability and formation of non-bilayer structures in CL-enriched membranes that biochemically mimic the outer and inner mitochondrial membranes. Finally, molecular dynamics simulations and in silico docking studies identified CL binding sites in cardiotoxin VII4 and revealed a molecular mechanism by which cardiotoxin VII4 interacts with CL and PC to bind and penetrate mitochondrial membranes.
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spelling doaj.art-a229952db70f4154ae0c09b08c9e5d7a2022-12-22T02:57:22ZengMDPI AGToxins2072-66512019-03-0111315210.3390/toxins11030152toxins11030152Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and FunctionBoris Zhang0Feng Li1Zhengyao Chen2Indira H. Shrivastava3Edward S. Gasanoff4Ruben K. Dagda5University of Nevada, Reno School of Medicine, Department of Pharmacology, Reno, NV 89557, USASTEM Program, Science Department, Chaoyang KaiWen Academy, North Dongba Road, Beijing 100016, ChinaSTEM Program, Science Department, Chaoyang KaiWen Academy, North Dongba Road, Beijing 100016, ChinaDepartment of Computational and System Biology, University of Pittsburgh, PA, 15260, USASTEM Program, Science Department, Chaoyang KaiWen Academy, North Dongba Road, Beijing 100016, ChinaUniversity of Nevada, Reno School of Medicine, Department of Pharmacology, Reno, NV 89557, USACobra venom cardiotoxins (CVCs) can translocate to mitochondria to promote apoptosis by eliciting mitochondrial dysfunction. However, the molecular mechanism(s) by which CVCs are selectively targeted to the mitochondrion to disrupt mitochondrial function remains to be elucidated. By studying cardiotoxin from Naja mossambica mossambica cobra (cardiotoxin VII4), a basic three-fingered S-type cardiotoxin, we hypothesized that cardiotoxin VII4 binds to cardiolipin (CL) in mitochondria to alter mitochondrial structure/function and promote neurotoxicity. By performing confocal analysis, we observed that red-fluorescently tagged cardiotoxin rapidly translocates to mitochondria in mouse primary cortical neurons and in human SH-SY5Y neuroblastoma cells to promote aberrant mitochondrial fragmentation, a decline in oxidative phosphorylation, and decreased energy production. In addition, by employing electron paramagnetic resonance (EPR) and protein nuclear magnetic resonance (1H-NMR) spectroscopy and phosphorescence quenching of erythrosine in model membranes, our compiled biophysical data show that cardiotoxin VII4 binds to anionic CL, but not to zwitterionic phosphatidylcholine (PC), to increase the permeability and formation of non-bilayer structures in CL-enriched membranes that biochemically mimic the outer and inner mitochondrial membranes. Finally, molecular dynamics simulations and in silico docking studies identified CL binding sites in cardiotoxin VII4 and revealed a molecular mechanism by which cardiotoxin VII4 interacts with CL and PC to bind and penetrate mitochondrial membranes.http://www.mdpi.com/2072-6651/11/3/152cobra cardiotoxinmitochondriacardiolipinmitochondrial dysfunctionnon-bilayer membrane structures
spellingShingle Boris Zhang
Feng Li
Zhengyao Chen
Indira H. Shrivastava
Edward S. Gasanoff
Ruben K. Dagda
Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function
Toxins
cobra cardiotoxin
mitochondria
cardiolipin
mitochondrial dysfunction
non-bilayer membrane structures
title Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function
title_full Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function
title_fullStr Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function
title_full_unstemmed Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function
title_short Naja mossambica mossambica Cobra Cardiotoxin Targets Mitochondria to Disrupt Mitochondrial Membrane Structure and Function
title_sort naja mossambica mossambica cobra cardiotoxin targets mitochondria to disrupt mitochondrial membrane structure and function
topic cobra cardiotoxin
mitochondria
cardiolipin
mitochondrial dysfunction
non-bilayer membrane structures
url http://www.mdpi.com/2072-6651/11/3/152
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