Figure 5.

An overview of the roles of Rab GTPases in CoV infection. After internalization, CoVs are delivered to suitable endosomes and follow the intracellular pathway of the endosomal/lysosomal system with diverse Rab GTPases involved. Subsequently, CoVs fuse at the designated locations, such as MERS-CoV and PHEV fusion, which both occur in the early endosome; PEDV fusion mainly occurs in the late endosome; MHV and FIPV fusions occur in the lysosome. In addition, Rab GTPases also play an important role in CoV replication and egress. For example, the replication of PHEV and PDCoV genomes needs the help of Rab5 and Rab7, and IBV, as a well-established model virus used to investigate the pathway of CoV, egress from host cells needs to employ Rab1 and Rab11. Abbreviations—MERS-CoV: Middle East respiratory syndrome coronavirus; PHEV: hemagglutinating encephalomyelitis virus; PEDV: porcine epidemic diarrhea virus; MHV: mouse hepatitis coronavirus; PDCoV: porcine deltacoronavirus; FIPV: feline infectious peritonitis virus.