NOD2 Protein, Human (sf9, Strep, Flag)

NOD2 is a pattern recognition receptor (PRR) that detects bacterial peptidoglycan fragments and danger signals, playing a key role in gastrointestinal immunity. It is specifically activated by muramyl dipeptide (MDP), a universal bacterial peptidoglycan component, and binds its phosphorylated form, 6-O-phospho-MDP. This binding triggers oligomerization, recruiting and activating RIPK2, which undergoes ubiquitination by E3 ligases (XIAP, BIRC2, BIRC3, and LUBAC), leading to NF-kappa-B and MAP kinase signaling activation and immune gene transcription. NOD2 maintains gut microbiota-host immune balance via MDP sensing (by similar). Dysregulation causes dysbiosis, epithelial barrier damage, and inflammation (by similar). It also regulates appetite by sensing MDP in brain neurons, suppressing neuronal activity to modulate satiety and body temperature (by similar). Under malnutrition, intestinal MDP sensing supports postnatal growth (by similar). NOD2 senses viral ssRNA, interacting with MAVS to activate IRF3 and type I interferon. It modulates dendritic cell autophagy via ATG16L1 and promotes intestinal stem cell survival (by similar). Additionally, NOD2 responds to endoplasmic reticulum stress by detecting sphingosine-1-phosphate, initiating inflammatory signaling, and may activate NLRP1 in macrophages, leading to CASP1 activation and IL1B release.