CDB25:0003967 NAMPT — TLR4

Experimentally validated in Human, Mixed species; Orthology-inferred in Human, Mouse, Rat, Frog, Chicken, Macaque, Pig, Dog, Cow, Chimp, Horse, Marmoset, Sheep

Title

Journal:; Year Published:

Abstract

Unique Toll-Like Receptor 4 Activation by NAMPT/PBEF Induces NFκB Signaling and Inflammatory Lung Injury.

Scientific reports, 2015; PubMed, Homo sapiens NAMPT — Homo sapiens TLR4
ABSTRACT: Ventilator-induced inflammatory lung injury (VILI) is mechanistically linked to increased NAMPT transcription and circulating levels of nicotinamide phosphoribosyl-transferase (NAMPT/PBEF). Although VILI severity is attenuated by reduced NAMPT/PBEF bioavailability, the precise contribution of NAMPT/PBEF and excessive mechanical stress to VILI pathobiology is unknown. We now report that NAMPT/PBEF induces lung NFκB transcriptional activities and inflammatory injury via direct ligation of Toll-like receptor 4 (TLR4). Computational analysis demonstrated that NAMPT/PBEF and MD-2, a TLR4-binding protein essential for LPS-induced TLR4 activation, share ~30% sequence identity and exhibit striking structural similarity in loop regions critical for MD-2-TLR4 binding. Unlike MD-2, whose TLR4 binding alone is insufficient to initiate TLR4 signaling, NAMPT/PBEF alone produces robust TLR4 activation, likely via a protruding region of NAMPT/PBEF (S402-N412) with structural similarity to LPS. The identification of this unique mode of TLR4 activation by NAMPT/PBEF advances the understanding of innate immunity responses as well as the untoward events associated with mechanical stress-induced lung inflammation.
Basic Information on NAMPT
Ligand Name: nicotinamide phosphoribosyltransferase
Other Symbols: PBEF1, PBEF
Ligand Location: secreted based on hpa, perplexity, uniprot
HGNC Gene Symbol Report: NAMPT
GeneCards: NAMPT
HGNC Gene Group: unknown
Interactions with other Receptors for NAMPT
Basic Information on TLR4
Receptor Name: toll like receptor 4
Other Symbols: hToll, CD284, TLR-4, ARMD10
Receptor Location: cell membrane based on hpa, perplexity, uniprot
HGNC Gene Symbol Report: TLR4
GeneCards: TLR4