Cytolethal distending toxins require components of the ER-associated degradation pathway for host cell entry.

Authors:
Aria Eshraghi
Aria Eshraghi
University of California
Tempe | United States
Shandee D Dixon
Shandee D Dixon
University of Michigan Medical School
United States
Batcha Tamilselvam
Batcha Tamilselvam
University of Illinois
United States
Emily Jin-Kyung Kim
Emily Jin-Kyung Kim
University of California
Santa Barbara | United States
Amandeep Gargi
Amandeep Gargi
University of California
United States
Julia C Kulik
Julia C Kulik
University of California
Oakland | United States
Robert Damoiseaux
Robert Damoiseaux
University of California
United States
Steven R Blanke
Steven R Blanke
University of Illinois
United States

PLoS Pathog 2014 Jul 31;10(7):e1004295. Epub 2014 Jul 31.

Department of Microbiology, Immunology and Molecular Genetics, University of California, Los Angeles, Los Angeles, California, United States of America; California NanoSystems Institute, University of California, Los Angeles, Los Angeles, California, United States of America.

Intracellular acting protein exotoxins produced by bacteria and plants are important molecular determinants that drive numerous human diseases. A subset of these toxins, the cytolethal distending toxins (CDTs), are encoded by several Gram-negative pathogens and have been proposed to enhance virulence by allowing evasion of the immune system. CDTs are trafficked in a retrograde manner from the cell surface through the Golgi apparatus and into the endoplasmic reticulum (ER) before ultimately reaching the host cell nucleus. However, the mechanism by which CDTs exit the ER is not known. Here we show that three central components of the host ER associated degradation (ERAD) machinery, Derlin-2 (Derl2), the E3 ubiquitin-protein ligase Hrd1, and the AAA ATPase p97, are required for intoxication by some CDTs. Complementation of Derl2-deficient cells with Derl2:Derl1 chimeras identified two previously uncharacterized functional domains in Derl2, the N-terminal 88 amino acids and the second ER-luminal loop, as required for intoxication by the CDT encoded by Haemophilus ducreyi (Hd-CDT). In contrast, two motifs required for Derlin-dependent retrotranslocation of ERAD substrates, a conserved WR motif and an SHP box that mediates interaction with the AAA ATPase p97, were found to be dispensable for Hd-CDT intoxication. Interestingly, this previously undescribed mechanism is shared with the plant toxin ricin. These data reveal a requirement for multiple components of the ERAD pathway for CDT intoxication and provide insight into a Derl2-dependent pathway exploited by retrograde trafficking toxins.

Download full-text PDF

Source
http://dx.doi.org/10.1371/journal.ppat.1004295DOI Listing
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC4117610PMC
July 2014
1 Read

Publication Analysis

Top Keywords

aaa atpase
8
host cell
8
distending toxins
8
required intoxication
8
cytolethal distending
8
atpase p97
8
associated degradation
4
degradation erad
4
host associated
4
dispensable hd-cdt
4
components host
4
p97 dispensable
4
central components
4
derlin-2 derl2
4
mediates interaction
4
ligase hrd1
4
hrd1 aaa
4
ubiquitin-protein ligase
4
derl2 ubiquitin-protein
4
machinery derlin-2
4

Similar Publications

Cellular interactions of the cytolethal distending toxins from Escherichia coli and Haemophilus ducreyi.

J Biol Chem 2013 Mar 10;288(11):7492-505. Epub 2013 Jan 10.

Department of Microbiology, University of Illinois, Urbana, Illinois 61801, USA.

The cytolethal distending toxins (CDTs) compose a subclass of intracellularly acting genotoxins produced by many Gram-negative pathogenic bacteria that disrupt the normal progression of the eukaryotic cell cycle. Here, the intoxication mechanisms of CDTs from Escherichia coli (Ec-CDT) and Haemophilus ducreyi (Hd-CDT), which share limited amino acid sequence homology, were directly compared. Ec-CDT and Hd-CDT shared comparable in vitro DNase activities of the CdtB subunits, saturable cell surface binding with comparable affinities, and the requirement for an intact Golgi complex to induce cell cycle arrest. Read More

View Article
March 2013

Cytolethal distending toxin family members are differentially affected by alterations in host glycans and membrane cholesterol.

J Biol Chem 2010 Jun 12;285(24):18199-207. Epub 2010 Apr 12.

Department of Microbiology, University of California, Los Angeles, California 90095, USA.

Cytolethal distending toxins (CDTs) are tripartite protein exotoxins produced by a diverse group of pathogenic Gram-negative bacteria. Based on their ability to induce DNA damage, cell cycle arrest, and apoptosis of cultured cells, CDTs are proposed to enhance virulence by blocking cellular division and/or directly killing epithelial and immune cells. Despite the widespread distribution of CDTs among several important human pathogens, our understanding of how these toxins interact with host cells is limited. Read More

View Article
June 2010

Cellular internalization of cytolethal distending toxin: a new end to a known pathway.

Cell Microbiol 2005 Jul;7(7):921-34

Microbiology and Tumorbiology Center, Karolinska Institutet, Stockholm, Sweden.

The cytolethal distending toxins (CDTs) are unique in their ability to induce DNA damage, activate checkpoint responses and cause cell cycle arrest or apoptosis in intoxicated cells. However, little is known about their cellular internalization pathway. We demonstrate that binding of the Haemophilus ducreyi CDT (HdCDT) on the plasma membrane of sensitive cells was abolished by cholesterol extraction with methyl-beta-cyclodextrin. Read More

View Article
July 2005

Mouse Mammary Tumor Virus Signal Peptide Uses a Novel p97-Dependent and Derlin-Independent Retrotranslocation Mechanism To Escape Proteasomal Degradation.

MBio 2017 03 28;8(2). Epub 2017 Mar 28.

Department of Molecular Biosciences, The University of Texas at Austin, Austin, Texas, USA

Multiple pathogens, including viruses and bacteria, manipulate endoplasmic reticulum-associated degradation (ERAD) to avoid the host immune response and promote their replication. The betaretrovirus mouse mammary tumor virus (MMTV) encodes Rem, which is a precursor protein that is cleaved into a 98-amino-acid signal peptide (SP) and a C-terminal protein (Rem-CT). SP uses retrotranslocation for ER membrane extraction and yet avoids ERAD by an unknown mechanism to enter the nucleus and function as a Rev-like protein. Read More

View Article
March 2017