Positive-strand RNA viruses subvert the cellular endomembrane system for the generation of distinct compartments termed replication organelles (ROs) that harbor the site where viral RNAs are generated. In this study, we corroborate that the SARS-CoV-2 non-structural proteins 3 and 4 (nsp3 and nsp4) suffice to remodel the endoplasmic reticulum to form double-membrane vesicles similar to ROs observed in viral infection. Cellular membrane alterations induced by nsp3/4 expression were …