The COX4I2 antibody is a valuable tool for studying the cytochrome c oxidase subunit 4 isoform 2 (COX4I2), a tissue-specific component of mitochondrial Complex IV in the electron transport chain. Unlike its ubiquitous isoform COX4I1. COX4I2 is predominantly expressed in oxygen-sensitive or metabolically specialized tissues, such as lung, placenta, and vascular smooth muscle cells. This isoform plays a critical role in adapting cellular respiration to low oxygen conditions, potentially influencing oxygen-sensing pathways and metabolic flexibility. Researchers employ COX4I2 antibodies to investigate its expression patterns, subcellular localization, and regulatory functions under hypoxia or pathological states like pulmonary hypertension and cancer. These antibodies are typically validated for techniques including Western blotting, immunohistochemistry, and immunofluorescence. Studies using COX4I2-specific reagents have revealed its association with metabolic reprogramming in tumors and its potential as a biomarker for hypoxia-related diseases. Ongoing research focuses on its structural differences from COX4I1. tissue-specific regulatory mechanisms, and therapeutic implications in mitochondrial disorders.