GRIM-19 Interacts with Nucleotide Oligomerization Domain 2 and Serves as Downstream Effector of Anti-bacterial Function in Intestinal Epithelial Cells

Nicolas Barnich,Tadakazu Hisamatsu,Jose E Aguirre,Ramnik Xavier,Hans-Christian Reinecker,Daniel K Podolsky

doi:10.1074/jbc.m413776200

Nicolas Barnich, Tadakazu Hisamatsu + Show 4 more

Open Access

https://doi.org/10.1074/jbc.m413776200

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Abstract

Nucleotide oligomerization domain 2 (NOD2) functions as a mammalian cytosolic pathogen recognition molecule, and variants have been associated with risk for Crohn disease. We recently demonstrated that NOD2 functions as an anti-bacterial factor limiting survival of intracellular invasive bacteria. To gain further insight into the mechanism of NOD2 activation and signal transduction, we performed yeast two-hybrid screening. We demonstrate that GRIM-19, a protein with homology to the NADPH dehydrogenase complex, interacts with endogenous NOD2 in HT29 cells. GRIM-19 is required for NF-kappaB activation following NOD2-mediated recognition of bacterial muramyl dipeptide. GRIM-19 also controls pathogen invasion of intestinal epithelial cells. GRIM-19 expression is decreased in inflamed mucosa of patients with inflammatory bowel diseases. GRIM-19 may be a key component in NOD2-mediated innate mucosal responses and serve to regulate intestinal epithelial cell responses to microbes.

Highlights

Crohn disease (CD)1 is an inflammatory bowel disease (IBD) characterized by chronic inflammation of the intestine
Co-expression of Nucleotide oligomerization domain 2 (NOD2) and GRIM-19 in yeast survival assays in S.D./ϪAde/ ϪHis/ϪLeu/ϪTrp/X-gal-selective medium confirmed a strong interaction between these two proteins
We have previously shown that NOD2, but not the NOD2 mutant 3020insC associated with CD, protects intestinal epithelial cells against Salmonella infection [19]

Summary

Introduction

Crohn disease (CD) is an inflammatory bowel disease (IBD) characterized by chronic inflammation of the intestine. Recent studies leave unclear whether NOD2 is a regulator of TLR2 responses that may be disregulated when NOD2 3020insC mutant associated with CD is present (14 –16). A direct interaction between NOD2 and transforming growth factor-␤-activated kinase 1 (TAK1) was recently shown, and TAK1 regulates NOD2-mediated NF-␬B activation [17]. A recent study of NOD2-deficient mice shows loss of protective immunity in response to bacterial muramyl dipeptide [15]. These mice are susceptible to listeria infection via the oral route. We have previously shown that the 3020insC mutant of CARD15/ NOD2 has impaired function as a defensive factor against intracellular bacteria in intestinal epithelial cells (IEC) [19]. We demonstrate here that GRIM-19 is an interactor necessary for NF-␬B and anti-bacterial effects of NOD2

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