Coronaviruses (CoVs) are enveloped viruses with a positive-sense, single-stranded RNA genome. They primarily infect birds and mammals, causing various diseases, but have also infected humans, leading to severe respiratory illnesses like SARS and MERS. Recent research has focused on the CoV envelope (E) protein, a small, integral membrane protein involved in viral assembly, budding, and pathogenesis. The E protein is a viroporin, forming ion channels and interacting with both viral and host proteins. While much progress has been made in understanding the E protein's structure, function, and interactions, many aspects remain unclear. The E protein is crucial for viral assembly and maturation, and its absence can make CoVs promising vaccine candidates. The E protein's role in pathogenesis is also significant, with its interactions influencing viral spread and host cell processes. The E protein's topology varies among CoVs, and its localization is primarily in the ER-Golgi region. Post-translational modifications like palmitoylation and myristoylation affect its function and localization. The E protein also interacts with host proteins, such as Bcl-xL and PALS1, contributing to viral pathogenesis. The E protein's role in membrane curvature and viral budding is also under investigation. Despite these findings, many aspects of the E protein's function and interactions remain to be determined, highlighting the need for further research to develop effective antiviral strategies against CoVs.Coronaviruses (CoVs) are enveloped viruses with a positive-sense, single-stranded RNA genome. They primarily infect birds and mammals, causing various diseases, but have also infected humans, leading to severe respiratory illnesses like SARS and MERS. Recent research has focused on the CoV envelope (E) protein, a small, integral membrane protein involved in viral assembly, budding, and pathogenesis. The E protein is a viroporin, forming ion channels and interacting with both viral and host proteins. While much progress has been made in understanding the E protein's structure, function, and interactions, many aspects remain unclear. The E protein is crucial for viral assembly and maturation, and its absence can make CoVs promising vaccine candidates. The E protein's role in pathogenesis is also significant, with its interactions influencing viral spread and host cell processes. The E protein's topology varies among CoVs, and its localization is primarily in the ER-Golgi region. Post-translational modifications like palmitoylation and myristoylation affect its function and localization. The E protein also interacts with host proteins, such as Bcl-xL and PALS1, contributing to viral pathogenesis. The E protein's role in membrane curvature and viral budding is also under investigation. Despite these findings, many aspects of the E protein's function and interactions remain to be determined, highlighting the need for further research to develop effective antiviral strategies against CoVs.