NLRX1 or NLR family member X1, short for nucleotide-binding oligomerization domain, leucine rich repeat containing X1, is an intracellular

Intracellular

Not to be confused with intercellular, meaning "between cells".In cell biology, molecular biology and related fields, the word intracellular means "inside the cell".It is used in contrast to extracellular...

 protein that plays a role in the immune system

Immune system

An immune system is a system of biological structures and processes within an organism that protects against disease by identifying and killing pathogens and tumor cells. It detects a wide variety of agents, from viruses to parasitic worms, and needs to distinguish them from the organism's own...

. It is also known as NOD-like receptor X1, NLR family, X1, NOD5, NOD9, and CLR11.3, and is a member of the NOD-like receptor family of pattern recognition receptor

Pattern recognition receptor

Pattern recognition receptors are a primitive part of the immune system. They are proteins expressed by cells of the innate immune system to identify pathogen-associated molecular patterns , which are associated with microbial pathogens or cellular stress, as well as damage-associated molecular...

s. NLRX1 affects innate immunity to virus

Virus

A virus is a small infectious agent that can replicate only inside the living cells of organisms. Viruses infect all types of organisms, from animals and plants to bacteria and archaea...

es by interfering with the mitochondrial antiviral signaling protein (MAVS

VISA (gene)

Mitochondrial antiviral-signaling protein is a protein that in humans is encoded by the MAVS gene. The protein is also known by the names VISA, IPS-1 and Cardif. Aggregated MAVS form protease resistant prion-like aggregates that activate IRF3 dimerization. - NCBI Refseq summary of MAVS :-Further...

)/retinoic-acid-inducible gene I (RIG-I) mitochondrial antiviral pathway.

NLRX1 has a unique protein structure composed of 3 protein domain

Protein domain

A protein domain is a part of protein sequence and structure that can evolve, function, and exist independently of the rest of the protein chain. Each domain forms a compact three-dimensional structure and often can be independently stable and folded. Many proteins consist of several structural...

s: an N-terminal effector domain containing a mitochondrion localization signal; a central NACHT domain

NACHT domain

The NACHT domain is an evolutionary conserved protein domain.This NTPase domain is found in apoptosis proteins as well as those involved in MHC transcription....

; a C-terminal leucine-rich repeat

Leucine-rich repeat

A leucine-rich repeat is a protein structural motif that forms an α/β horseshoe fold. It is composed of repeating 20–30 amino acid stretches that are unusually rich in the hydrophobic amino acid leucine...

 (LRR) domain.

In humans, the NLRX1 protein is encoded by the NLRX1 gene

Gene

A gene is a molecular unit of heredity of a living organism. It is a name given to some stretches of DNA and RNA that code for a type of protein or for an RNA chain that has a function in the organism. Living beings depend on genes, as they specify all proteins and functional RNA chains...

.