Many positive stranded RNA viruses traffic from cell surface into endosomes and then from endosomes onto the surface of the ER. They generate ER-wrapped replication centers on the cytoplasmic surface of the ER. We aim to understand the membrane trafficking pathway these viruses traffic across the endosomal membrane and onto the surface of the ER and whether this process is facilitated by membrane contact sites. On the ER, we aim to unravel what ER proteins are used to wrap ER membranes around the virus to form the functional replication center. We will use fluorescence microscopy, electron microscopy and biochemical methods to unravel the path and machinery involved.