Gene

Cell biology

Intracellular parasite

Mitophagy

Bacteria

Biology

Virulence factor

Apoptosis

Autophagy

Listeria

Intracellular

Genetics

Listeria monocytogenes

Microbiology

Mitochondrion

Listeriolysin O

Virulence

Nature Immunology

Cells use mitophagy to remove damaged or unwanted mitochondria to maintain homeostasis. Here we report that the intracellular bacterial pathogen Listeria monocytogenes exploits host mitophagy to evade killing. We found that L. monocytogenes induced mitophagy in macrophages through the virulence factor listeriolysin O (LLO). We discovered that NLRX1, the only Nod-like receptor (NLR) family member with a mitochondrial targeting sequence, contains an LC3-interacting region (LIR) and directly associated with LC3 through the LIR. NLRX1 and its LIR motif were essential for L. monocytogenes–induced mitophagy. NLRX1 deficiency and use of a mitophagy inhibitor both increased mitochondrial production of reactive oxygen species and thereby suppressed the survival of L. monocytogenes. Mechanistically, L. monocytogenes and LLO induced oligomerization of NLRX1 to promote binding of its LIR motif to LC3 for induction of mitophagy. Our study identifies NLRX1 as a novel mitophagy receptor and discovers a previously unappreciated strategy used by pathogens to hijack a host cell homeostasis system for their survival. Removal of damaged mitochondria maintains cellular homeostasis and regulates inflammation. Qian and colleagues describe a mechanism by which intracellular bacteria such as Listeria can elicit mitophagy to enable their survival.

Listeria hijacks host mitophagy through a novel mitophagy receptor to evade killing