GJA3 and pulmonary hypertension: Vascular and hematological adaptation mechanisms were reflected in LTBP2’s regulation of TGF-β-mediated vascular remodeling to increase pulmonary artery elasticity, preventing high-altitude pulmonary hypertension, while GJA3 maintained gap junction communication to coordinate cardiomyocyte electrophysiological synchronization under hypoxia, showing strong association with cardiac hypoxia tolerance.