NMRK2 (nicotinamide riboside kinase 2) is a key enzyme in NAD+ biosynthesis that catalyzes the phosphorylation of nicotinamide riboside to form nicotinamide mononucleotide, serving as an essential component of cellular energy metabolism 1. The enzyme functions as both a metabolic regulator and structural protein, with a short isoform known as muscle integrin binding protein (MIBP) that interacts with the α7β1 integrin complex and regulates laminin matrix deposition 2. NMRK2 expression is significantly upregulated in response to energy stress and is regulated by AMP-activated protein kinase and peroxisome proliferator-activated receptor α 1. In cardiac tissue, NMRK2 provides critical protection against ischemia/reperfusion injury by enhancing cellular antioxidant capacity through a YAP-NADK signaling axis that increases NADPH levels and maintains redox homeostasis 3. The gene shows particular clinical relevance in dilated cardiomyopathy, where it becomes essential for cardiac function during aging and NAD+ homeostasis maintenance 2. In cancer, NMRK2 is transcriptionally activated by TFE3 fusion proteins in Xp11.2 translocation renal cell carcinomas, serving both as a diagnostic biomarker and promoting tumor progression through enhanced mitochondrial respiration 45. Additionally, NMRK2 contributes to immune evasion in certain cancers by impairing CD8+ T cell function through NAD+-dependent mechanisms 6.