Biology Reference
In-Depth Information
Chapter 22
Astrovirus Replication: An Overview
Susana Guix
†
, Albert Bosch
*
,†
and Rosa M. Pintó
†
Human astroviruses are important pathogens that cause gastroenteritis world-
wide. Significant progress has recently been made regarding the characteri-
zation of the RNA replication process, the apoptotic response induced in
virus-infected cells, and the formation of virus-like particles. First, a rela-
tionship between astrovirus RNA replication sites and the endoplasmic
reticulum-derived membranes has been suggested. In addition, a direct rela-
tionship 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
3 icosahedral capsid. The C-terminal half of the capsid polyprotein —
highly variable between different astroviruses — is thought to form the
receptor-interaction domain.
T
=
Background for Human Astroviruses
Infections of the gastrointestinal tract cause approximately two billion
cases of diarrhea in children per year worldwide, with the majority of
*Corresponding author: Albert Bosch, Department of Microbiology, University of Barcelona,
Avda Diagonal 645, 08028 Barcelona, Spain, E-mail: abosch@ub.edu.
†
Enteric Virus Group, Department of Microbiology, University of Barcelona.
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