VPS4A and viral infectious disease: Two types of VPS4 complexes, VPS4A and VPS4B, have been identified in mammals, and they play important roles in cell biology and disease, including cell division (Morita et al., 2010), membrane fusion and fission (Finken-Eigen et al., 1997; Migliano and Teis, 2018), and viral infection (Kieffer et al., 2008; Broniarczyk et al., 2017) among other biological processes.