Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis

ABSTRACT The ability of diarrheagenic bacterial pathogens, such as enteropathogenic Escherichia coli (EPEC), to modulate the activity of mitogen-activated protein kinases (MAPKs) and cell survival has been suggested to benefit bacterial colonization and infection. However, our understanding of the m...

Full description

Bibliographic Details
Main Authors: Rachana Pattani Ramachandran, Chaya Spiegel, Yael Keren, Tsafi Danieli, Naomi Melamed-Book, Ritesh Ranjan Pal, Efrat Zlotkin-Rivkin, Ilan Rosenshine, Benjamin Aroeti
Format: Article
Language:English
Published: American Society for Microbiology 2020-10-01
Series:mBio
Subjects:
Online Access:https://journals.asm.org/doi/10.1128/mBio.01397-20
_version_ 1818740340360740864
author Rachana Pattani Ramachandran
Chaya Spiegel
Yael Keren
Tsafi Danieli
Naomi Melamed-Book
Ritesh Ranjan Pal
Efrat Zlotkin-Rivkin
Ilan Rosenshine
Benjamin Aroeti
author_facet Rachana Pattani Ramachandran
Chaya Spiegel
Yael Keren
Tsafi Danieli
Naomi Melamed-Book
Ritesh Ranjan Pal
Efrat Zlotkin-Rivkin
Ilan Rosenshine
Benjamin Aroeti
author_sort Rachana Pattani Ramachandran
collection DOAJ
description ABSTRACT The ability of diarrheagenic bacterial pathogens, such as enteropathogenic Escherichia coli (EPEC), to modulate the activity of mitogen-activated protein kinases (MAPKs) and cell survival has been suggested to benefit bacterial colonization and infection. However, our understanding of the mechanisms by which EPEC modulate these functions is incomplete. In this study, we show that the EPEC type III secreted effector Map stimulates the sheddase activity of the disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) and the ERK and p38 MAPK signaling cascades. Remarkably, all these activities were dependent upon the ability of Map to target host mitochondria, mainly via its mitochondrial toxicity region (MTR). Map targeting of mitochondria disrupted the mitochondrial membrane potential, causing extrusion of mitochondrial Ca2+ into the host cell cytoplasm. We also found that Map targeting of mitochondria is essential for triggering host cell apoptosis. Based on these findings, we propose a model whereby Map imported into mitochondria causes mitochondrial dysfunction and Ca2+ efflux into the host cytoplasm. Since Ca2+ has been reported to promote ADAM10 activation, the acute elevation of Ca2+ in the cytoplasm may stimulate the ADAM10 sheddase activity, resulting in the release of epidermal growth factors that stimulate the ERK signaling cascade. As p38 activity is also Ca2+ sensitive, elevation in cytoplasmic Ca2+ may independently also activate p38. We hypothesize that Map-dependent MAPK activation, combined with Map-mediated mitochondrial dysfunction, evokes mitochondrial host cell apoptosis, potentially contributing to EPEC colonization and infection of the gut. IMPORTANCE Enteropathogenic E. coli (EPEC) is an important human diarrhea-causing bacterium. The pathogenic effects of EPEC largely depend upon its ability to inject a series of proteins, termed effectors, into the host cells. One such effector is the mitochondrion-associated protein (Map). Map has been shown to induce actin-rich projections (i.e., filopodia) on the infected cell surface and activate a Rho GTPase enzyme termed Cdc42. Nonetheless, although most injected Map localizes to host mitochondria, its functions in the mitochondria remain unknown. Here, we show that Map targeting of mitochondria stimulates the disruption of mitochondrial membrane potential to induce Ca2+ efflux into the host cytoplasm. The efflux stimulates the activity of a protein termed ADAM10, which induces activation of a mitogen-activated protein kinase cascade leading to host cell apoptosis. As apoptosis plays a central role in host-pathogen interactions, our findings provide novel insights into the functions of mitochondrial Map in promoting the EPEC disease.
first_indexed 2024-12-18T01:39:10Z
format Article
id doaj.art-69985f54fb95449582d31c23b511ca9f
institution Directory Open Access Journal
issn 2150-7511
language English
last_indexed 2024-12-18T01:39:10Z
publishDate 2020-10-01
publisher American Society for Microbiology
record_format Article
series mBio
spelling doaj.art-69985f54fb95449582d31c23b511ca9f2022-12-21T21:25:24ZengAmerican Society for MicrobiologymBio2150-75112020-10-0111510.1128/mBio.01397-20Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell ApoptosisRachana Pattani Ramachandran0Chaya Spiegel1Yael Keren2Tsafi Danieli3Naomi Melamed-Book4Ritesh Ranjan Pal5Efrat Zlotkin-Rivkin6Ilan Rosenshine7Benjamin Aroeti8Department of Cell and Developmental Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelDepartment of Cell and Developmental Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelThe Protein Production Facility, Wolfson Centre for Applied Structural Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelThe Protein Production Facility, Wolfson Centre for Applied Structural Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelBioimaging Unit, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelDepartment of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, IsraelDepartment of Cell and Developmental Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelDepartment of Microbiology and Molecular Genetics, Institute for Medical Research Israel-Canada, Faculty of Medicine, The Hebrew University of Jerusalem, Jerusalem, IsraelDepartment of Cell and Developmental Biology, Alexander Silberman Institute of Life Sciences, The Hebrew University of Jerusalem, Jerusalem, IsraelABSTRACT The ability of diarrheagenic bacterial pathogens, such as enteropathogenic Escherichia coli (EPEC), to modulate the activity of mitogen-activated protein kinases (MAPKs) and cell survival has been suggested to benefit bacterial colonization and infection. However, our understanding of the mechanisms by which EPEC modulate these functions is incomplete. In this study, we show that the EPEC type III secreted effector Map stimulates the sheddase activity of the disintegrin and metalloproteinase domain-containing protein 10 (ADAM10) and the ERK and p38 MAPK signaling cascades. Remarkably, all these activities were dependent upon the ability of Map to target host mitochondria, mainly via its mitochondrial toxicity region (MTR). Map targeting of mitochondria disrupted the mitochondrial membrane potential, causing extrusion of mitochondrial Ca2+ into the host cell cytoplasm. We also found that Map targeting of mitochondria is essential for triggering host cell apoptosis. Based on these findings, we propose a model whereby Map imported into mitochondria causes mitochondrial dysfunction and Ca2+ efflux into the host cytoplasm. Since Ca2+ has been reported to promote ADAM10 activation, the acute elevation of Ca2+ in the cytoplasm may stimulate the ADAM10 sheddase activity, resulting in the release of epidermal growth factors that stimulate the ERK signaling cascade. As p38 activity is also Ca2+ sensitive, elevation in cytoplasmic Ca2+ may independently also activate p38. We hypothesize that Map-dependent MAPK activation, combined with Map-mediated mitochondrial dysfunction, evokes mitochondrial host cell apoptosis, potentially contributing to EPEC colonization and infection of the gut. IMPORTANCE Enteropathogenic E. coli (EPEC) is an important human diarrhea-causing bacterium. The pathogenic effects of EPEC largely depend upon its ability to inject a series of proteins, termed effectors, into the host cells. One such effector is the mitochondrion-associated protein (Map). Map has been shown to induce actin-rich projections (i.e., filopodia) on the infected cell surface and activate a Rho GTPase enzyme termed Cdc42. Nonetheless, although most injected Map localizes to host mitochondria, its functions in the mitochondria remain unknown. Here, we show that Map targeting of mitochondria stimulates the disruption of mitochondrial membrane potential to induce Ca2+ efflux into the host cytoplasm. The efflux stimulates the activity of a protein termed ADAM10, which induces activation of a mitogen-activated protein kinase cascade leading to host cell apoptosis. As apoptosis plays a central role in host-pathogen interactions, our findings provide novel insights into the functions of mitochondrial Map in promoting the EPEC disease.https://journals.asm.org/doi/10.1128/mBio.01397-20ADAM10calciumenteropathogenic E. coliMAP kinasesMap effectorprotein effectors
spellingShingle Rachana Pattani Ramachandran
Chaya Spiegel
Yael Keren
Tsafi Danieli
Naomi Melamed-Book
Ritesh Ranjan Pal
Efrat Zlotkin-Rivkin
Ilan Rosenshine
Benjamin Aroeti
Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis
mBio
ADAM10
calcium
enteropathogenic E. coli
MAP kinases
Map effector
protein effectors
title Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis
title_full Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis
title_fullStr Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis
title_full_unstemmed Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis
title_short Mitochondrial Targeting of the Enteropathogenic <named-content content-type="genus-species">Escherichia coli</named-content> Map Triggers Calcium Mobilization, ADAM10-MAP Kinase Signaling, and Host Cell Apoptosis
title_sort mitochondrial targeting of the enteropathogenic named content content type genus species escherichia coli named content map triggers calcium mobilization adam10 map kinase signaling and host cell apoptosis
topic ADAM10
calcium
enteropathogenic E. coli
MAP kinases
Map effector
protein effectors
url https://journals.asm.org/doi/10.1128/mBio.01397-20
work_keys_str_mv AT rachanapattaniramachandran mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT chayaspiegel mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT yaelkeren mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT tsafidanieli mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT naomimelamedbook mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT riteshranjanpal mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT efratzlotkinrivkin mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT ilanrosenshine mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis
AT benjaminaroeti mitochondrialtargetingoftheenteropathogenicnamedcontentcontenttypegenusspeciesescherichiacolinamedcontentmaptriggerscalciummobilizationadam10mapkinasesignalingandhostcellapoptosis