Hypoxia inducible NOD2 interacts with 3-O-sulfogalactoceramide and regulates vesicular homeostasis

© 2013..

BACKGROUND: Oxygen sensing in mammalian cells is a conserved signaling pathway regulated by hypoxia inducible factor type 1 (HIF-1). Inadequate oxygen supply (hypoxia) is common to many pathological disorders where autophagy plays an import role. The aim of this study was the identification and characterization of novel HIF-1 target genes that promote autophagy during hypoxia.

METHODS: Whole genome Chromatin Immune Precipitation from hypoxic HeLa cells was used to identify novel HIF-1 target genes. Hypoxia induced expression and transcription regulation was studied in wild type and HIF-deficient cells. siRNA silencing of candidate genes was used to establish their role during autophagy. Recombinant protein was used for screening immobilized glycosylated lipids to identify potential ligands.

RESULTS: We identified the Nucleotide Oligomerization Domain 2 (NOD2/CARD15) as a novel HIF-1 target and 3-O-sulfo-galactoceramide (sulfatide) and Mycobacterium sp. specific sulfolipid-1 as the first NOD2 ligands that both compete for binding to NOD2. Loss of NOD2 function impaired autophagy upstream of the autophagy inhibitor chloroquine by reducing the number of acidic vesicles. Inhibition of sulfatide synthesis elicited defects in autophagy similar to the NOD2 loss of function but did not influence NOD2-mediated NF-kB signaling.

CONCLUSIONS: Our findings suggest that the interaction of NOD2 with sulfatide may mediate the balance between autophagy and inflammation in hypoxic cells.

GENERAL SIGNIFICANCE: These findings may lead to a better understanding of complex inflammatory pathologies like Crohn's disease and tuberculosis where both NOD2 and hypoxia are implicated.

Medienart:

E-Artikel

Erscheinungsjahr:

2013

Erschienen:

2013

Enthalten in:

Zur Gesamtaufnahme - volume:1830

Enthalten in:

Biochimica et biophysica acta - 1830(2013), 11 vom: 23. Nov., Seite 5277-86

Sprache:

Englisch

Beteiligte Personen:

Nabatov, Alexey A [VerfasserIn]
Hatzis, Pantelis [VerfasserIn]
Rouschop, Kasper M A [VerfasserIn]
van Diest, Paul [VerfasserIn]
Vooijs, Marc [VerfasserIn]

Links:

Volltext

Themen:

53580-08-8
Autophagy
CQ
Chloroquine
Glycolipids
Hypoxia
Hypoxia-Inducible Factor 1, alpha Subunit
Journal Article
LRR
Leucine rich repeats
Ligands
MDP
Mtb
Muramyl dipeptide
Mycobacteria specific Sulfolipid-1
Mycobacterium tuberculosis
NF-kappa B
NOD2
NOD2 protein, human
Nod2 Signaling Adaptor Protein
Nucleotide-binding oligomerization domain-containing protein 2
PRR
Pathogen recognition receptors
Research Support, Non-U.S. Gov't
SL-1
Sulfatide
Sulfolipid I
V-ATPase
Vacuolar-type H(+)-ATPase
Vesicle
Virulence Factors

Anmerkungen:

Date Completed 21.03.2014

Date Revised 26.11.2016

published: Print-Electronic

Citation Status MEDLINE

doi:

10.1016/j.bbagen.2013.07.017

funding:

Förderinstitution / Projekttitel:

PPN (Katalog-ID):

NLM229403999