NINJ1
Description
The NINJ1 (ninjurin 1) is a protein-coding gene located on chromosome 9.
Ninjurin-1 is a protein that in humans is encoded by the NINJ1 gene.
NINJ1 (Ninjurin-1) plays a critical role in programmed cell death, particularly necroptosis and pyroptosis. It triggers plasma membrane rupture (cytolysis) by forming ring-like structures on the membrane and introducing hydrophilic alpha helices into the hydrophobic membrane. This action releases intracellular damage-associated molecular patterns (DAMPs), contributing to inflammation. NINJ1 also regulates Toll-like receptor 4 (TLR4) signaling by directly binding to lipopolysaccharide (LPS) during systemic inflammation. Furthermore, NINJ1 is involved in leukocyte migration, promoting the transendothelial migration of macrophages, particularly during inflammation in the central nervous system. Acting as a homophilic transmembrane adhesion molecule, NINJ1 plays a crucial role in various processes such as axonal growth, cell chemotaxis, and angiogenesis. This is achieved through its extracellular N-terminal adhesion motif (N-NAM) that mediates homophilic interactions. Additionally, NINJ1 promotes cell-to-cell interactions between immune cells and endothelial cells, contributing to the progression of inflammatory stress. It supports nerve regeneration by facilitating Schwann cell maturation. NINJ1 also acts as a regulator of angiogenesis, promoting the formation of new vessels through interactions between capillary pericyte cells and endothelial cells. Furthermore, it enhances the survival of prefusion osteoclasts, leading to osteoclast development. NINJ1 also participates in striated muscle growth and differentiation. A secreted form of NINJ1, generated by cleavage, possesses chemotactic activity and acts as an anti-inflammatory mediator by promoting monocyte recruitment, thereby ameliorating atherosclerosis. NINJ1 forms homooligomers that, in response to death stimuli, assemble into long, branched filaments and ring-shaped structures in the membrane.
NINJ1 is also known as NIN1, NINJURIN, hNINJ1.
