VMP1 (vacuole membrane protein 1) is an endoplasmic reticulum (ER)-localized transmembrane protein that functions as a phospholipid scramblase and regulates multiple cellular processes. VMP1 exhibits scramblase activity, controlling the distribution of cholesterol and phosphatidylserine across membranes 1. The protein plays essential roles in autophagosome formation by regulating ER-isolation membrane contacts through modulation of SERCA (sarco[endo]plasmic reticulum calcium ATPase) activity 2. VMP1 also controls cellular lipid and energy metabolism, including mitochondrial beta-oxidation and global metabolic regulation 3. Importantly, VMP1 serves as a crucial host factor required for infection by multiple RNA viruses, including all flaviviruses (such as dengue, Zika, and yellow fever viruses) and coronaviruses (including SARS-CoV-2) 45. During coronavirus infection, VMP1 facilitates the formation of double-membrane vesicles (DMVs) that serve as viral replication organelles, functioning specifically in the closure of zippered ER membranes into DMVs 6. The protein's role in maintaining cellular phosphatidylserine and cholesterol homeostasis likely contributes to its requirement for viral replication and organelle biogenesis 1.