Astrovirus Replication: An Overview

Human astroviruses are important pathogens that cause gastroenteritis worldwide. Significant progress has recently been made regarding the characterization of the RNA replication process, the apoptotic response induced in virus-infected cells, and the formation of virus-like particles. First, a relationship between astrovirus RNA replication sites and the endoplasmic reticulum-derived membranes has been suggested. In addition, a direct relationship between nonstructural proteins and the induction of apoptosis has been observed, and it has been demonstrated that apoptotic host cell death seems necessary for maturation of astrovirus particles. Finally, it has been predicted that the VP34 capsid protein contains the RNA binding domain at its N-terminus, responsible for packaging the viral genome, as well as an 8 β-barrel domain that may likely constitute the building subunit to form the T = 3 icosahedral capsid. The C-terminal half of the capsid polyprotein — highly variable between different astroviruses — is thought to form the receptor-interaction domain.