TY - JOUR
T1 - Binding of glutathione to enterovirus capsids is essential for virion morphogenesis
AU - Thibaut, Hendrik Jan
AU - van der Linden, Lonneke
AU - Jiang, Ping
AU - Thys, Bert
AU - Canela, María-Dolores
AU - Aguado, Leire
AU - Rombaut, Bart
AU - Wimmer, Eckard
AU - Paul, Aniko
AU - Pérez-Pérez, María-Jesús
AU - van Kuppeveld, Frank J M
AU - Neyts, Johan
PY - 2014/4
Y1 - 2014/4
N2 - Enteroviruses (family of the Picornaviridae) cover a large group of medically important human pathogens for which no antiviral treatment is approved. Although these viruses have been extensively studied, some aspects of the viral life cycle, in particular morphogenesis, are yet poorly understood. We report the discovery of TP219 as a novel inhibitor of the replication of several enteroviruses, including coxsackievirus and poliovirus. We show that TP219 binds directly glutathione (GSH), thereby rapidly depleting intracellular GSH levels and that this interferes with virus morphogenesis without affecting viral RNA replication. The inhibitory effect on assembly was shown not to depend on an altered reducing environment. Using TP219, we show that GSH is an essential stabilizing cofactor during the transition of protomeric particles into pentameric particles. Sequential passaging of coxsackievirus B3 in the presence of low GSH-levels selected for GSH-independent mutants that harbored a surface-exposed methionine in VP1 at the interface between two protomers. In line with this observation, enteroviruses that already contained this surface-exposed methionine, such as EV71, did not rely on GSH for virus morphogenesis. Biochemical and microscopical analysis provided strong evidence for a direct interaction between GSH and wildtype VP1 and a role for this interaction in localizing assembly intermediates to replication sites. Consistently, the interaction between GSH and mutant VP1 was abolished resulting in a relocalization of the assembly intermediates to replication sites independent from GSH. This study thus reveals GSH as a novel stabilizing host factor essential for the production of infectious enterovirus progeny and provides new insights into the poorly understood process of morphogenesis.
AB - Enteroviruses (family of the Picornaviridae) cover a large group of medically important human pathogens for which no antiviral treatment is approved. Although these viruses have been extensively studied, some aspects of the viral life cycle, in particular morphogenesis, are yet poorly understood. We report the discovery of TP219 as a novel inhibitor of the replication of several enteroviruses, including coxsackievirus and poliovirus. We show that TP219 binds directly glutathione (GSH), thereby rapidly depleting intracellular GSH levels and that this interferes with virus morphogenesis without affecting viral RNA replication. The inhibitory effect on assembly was shown not to depend on an altered reducing environment. Using TP219, we show that GSH is an essential stabilizing cofactor during the transition of protomeric particles into pentameric particles. Sequential passaging of coxsackievirus B3 in the presence of low GSH-levels selected for GSH-independent mutants that harbored a surface-exposed methionine in VP1 at the interface between two protomers. In line with this observation, enteroviruses that already contained this surface-exposed methionine, such as EV71, did not rely on GSH for virus morphogenesis. Biochemical and microscopical analysis provided strong evidence for a direct interaction between GSH and wildtype VP1 and a role for this interaction in localizing assembly intermediates to replication sites. Consistently, the interaction between GSH and mutant VP1 was abolished resulting in a relocalization of the assembly intermediates to replication sites independent from GSH. This study thus reveals GSH as a novel stabilizing host factor essential for the production of infectious enterovirus progeny and provides new insights into the poorly understood process of morphogenesis.
KW - Animals
KW - Capsid
KW - Cercopithecus aethiops
KW - Enterovirus B, Human
KW - Enterovirus Infections
KW - Glutathione
KW - HeLa Cells
KW - Humans
KW - Mutation
KW - RNA, Viral
KW - Vero Cells
KW - Virus Replication
U2 - 10.1371/journal.ppat.1004039
DO - 10.1371/journal.ppat.1004039
M3 - Article
C2 - 24722756
SN - 1553-7366
VL - 10
SP - e1004039
JO - PLoS Pathogens
JF - PLoS Pathogens
IS - 4
ER -