Next, we assessed the involvement of GPS1 in the late stages of infection, such as intracellular transport, viral assembly, viral particle formation, and budding, by examining the efficacy of formation of virus-like particles (VLPs), which are induced by the coexpression of the viral proteins hemagglutinin (HA), neuraminidase (NA), and M1 (36). The gene discussed is XK; the disease is infection.