Dataset Information

NleB host targets - The bacterial arginine glycosyltransferase effector NleB preferentially modifies Fas-associated death domain protein (FADD)

ABSTRACT: The inhibition of host innate immunity pathways is essential for the survival of attaching and effacing (A/E) pathogens such as enteropathogenic Escherichia coli (EPEC) and Citrobacter rodentium during mammalian infections. To subvert these pathways, A/E pathogens utilize a type III secretion system (T3SS) to introduce effectors that target key signaling pathways thereby suppressing the anti-microbial response. One effector used by A/E pathogens is the arginine glycosyltransferase NleB1 (NleBCR in C. rodentium) that modifies conserved arginine residues with N-acetylglucosamine (GlcNAc) in death-domain containing host proteins thereby blocking extrinsic apoptosis signaling. When expressed ectopically, NleB1 modifies the host proteins, FADD, TRADD and RIPK1. However, the true repertoire of arginine-GlcNAcylation during infection with endogenous levels of NleB delivered by the pathogen is unknown. Here we explored the effects of arginine-GlcNAcylation by NleB on the global host proteome. Utilizing an affinity proteomic approach for Arginine-GlcNAcylated glycopeptide, we compared the global repertoire of arginine-GlcNAcylation during ectopic expression of NleB, EPEC infection in vitro or C. rodentium infection in vivo. When NleB was overexpressed, multiple host proteins were arginine-GlcNAcylated. However, when endogenous levels of NleB were delivered during EPEC and C. rodentium infection, R117of FADD was rapidly and preferentially modified. The arginine-GlcNAcylation modification of FADD was extremely stable and insensitive to environmental or host cell degradation. Despite its stability and effect on the inhibition of apoptosis, arginine-GlcNAcylation did not illicit any proteomic changes, even in response to prolonged expression of NleB. Thus, under wild type levels of expression, NleB1/NleBCR antagonizes death-receptor-induced apoptosis of infected cells by modifying FADD in an irreversible and silent manner.

INSTRUMENT(S): Orbitrap Fusion Lumos, Q Exactive

ORGANISM(S): Homo Sapiens (human) Escherichia Coli Mus Musculus (mouse)

TISSUE(S): Epithelial Cell, Colon

SUBMITTER: Nichollas Scott

LAB HEAD: Elizabeth Hartland

PROVIDER: PXD006810 | Pride | 2017-09-11

REPOSITORIES: Pride

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Dataset's files

Source:

			Action	DRS
	Arg_GlcNAcSites-EPECendogenous.txt	Txt
	Arg_GlcNAcSites-EPECinfectionsOverexpression.txt	Txt
	Arg_GlcNAcSites-PRM_mouse.txt	Txt
	NSco_20170110_mouse_D4_colon_WT_1.raw	Raw
	NSco_20170110_mouse_D4_colon_delta_nleB_1.raw	Raw

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The bacterial arginine glycosyltransferase effector NleB preferentially modifies Fas-associated death domain protein (FADD).

Scott Nichollas E NE Giogha Cristina C Pollock Georgina L GL Kennedy Catherine L CL Webb Andrew I AI Williamson Nicholas A NA Pearson Jaclyn S JS Hartland Elizabeth L EL

The Journal of biological chemistry 20170831 42

The inhibition of host innate immunity pathways is essential for the persistence of attaching and effacing pathogens such as enteropathogenic <i>Escherichia coli</i> (EPEC) and <i>Citrobacter rodentium</i> during mammalian infections. To subvert these pathways and suppress the antimicrobial response, attaching and effacing pathogens use type III secretion systems to introduce effectors targeting key signaling pathways in host cells. One such effector is the arginine glycosyltransferase NleB1 (Nl ...[more]

PMID: 28860194

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