A positive-feedback mechanism promotes reovirus particle conversion to the intermediate associated with membrane penetration.
Proc Natl Acad Sci U S A
; 105(30): 10571-6, 2008 Jul 29.
Article
en En
| MEDLINE
| ID: mdl-18653761
ABSTRACT
Membrane penetration by reovirus is associated with conversion of a metastable intermediate, the ISVP, to a further-disassembled particle, the ISVP*. Factors that promote this conversion in cells are poorly understood. Here, we report the in vitro characterization of a positive-feedback mechanism for promoting ISVP* conversion. At high particle concentration, conversion approximated second-order kinetics, and products of the reaction operated in trans to promote the conversion of target ISVPs. Pore-forming peptide mu1N, which is released from particles during conversion, was sufficient for promoting activity. A mutant that does not undergo mu1N release failed to exhibit second-order conversion kinetics and also failed to promote conversion of wild-type target ISVPs. Susceptibility of target ISVPs to promotion in trans was temperature dependent and correlated with target stability, suggesting that capsid dynamics are required to expose the interacting epitope. A positive-feedback mechanism of promoting escape from the metastable intermediate has not been reported for other viruses but represents a generalizable device for sensing a confined volume, such as that encountered during cell entry.
Texto completo:
1
Banco de datos:
MEDLINE
Asunto principal:
Reoviridae
/
Membrana Celular
/
Retroalimentación Fisiológica
Tipo de estudio:
Prognostic_studies
/
Risk_factors_studies
Límite:
Animals
Idioma:
En
Año:
2008
Tipo del documento:
Article