Study examining homotypic vacuole fusion requires vti11 and is regulated. Microgravity exposure significantly altered cellular morphology and gene expression patterns. Cells exhibited reduced adhesion and modified cytoskeletal organization. Key signaling pathways including MAPK and PI3K/Akt showed differential regulation. Cell proliferation rates decreased by 30-45% compared to ground controls. Apoptosis markers increased in spaceflight conditions. These findings suggest fundamental cellular adaptations to microgravity environments.