Enhancement of polyhedrin nuclear localization during baculovirus infection.
AUTOR(ES)
Jarvis, D L
RESUMO
Polyhedrin is the major component of the nuclear viral occlusions produced during replication of the baculovirus Autographa californica multicapsid nuclear polyhedrosis virus (AcMNPV). Since viral occlusions are responsible for the horizontal transmission of AcMNPV in nature, the biosynthesis, localization, and assembly of polyhedrin are important events in the viral replication cycle. We recently defined the sequence requirements for nuclear localization and assembly of polyhedrin. In this study, we examined the localization of polyhedrin at different times of infection. The results showed that nuclear localization of polyhedrin becomes more efficient as the occlusion phase of infection progresses. Several different factors were identified that might contribute to this overall effect, including a higher rate of polyhedrin nuclear localization and a higher rate of polyhedrin biosynthesis. We also examined the biosynthesis and processing of polyhedrin in cells infected with an AcMNPV few polyhedra (FP) mutant, which produces smaller numbers of viral occlusions that contain few or no virions. Compared with wild type, the FP mutant produced polyhedrin more slowly and localized it to the nucleus less efficiently at the beginning of the occlusion phase of infection (24 h postinfection). This supported the idea that the efficiency of polyhedrin nuclear localization is tightly coupled to its rate of biosynthesis. It also revealed that expression of the viral 25K gene, which is inactivated in the FP mutant, is directly or indirectly associated with an enhancement of polyhedrin biosynthesis and nuclear localization at the beginning of the occlusion phase of infection. This enhancement effect appears to be necessary to ensure the normal assembly of viral occlusions.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=240310Documentos Relacionados
- Competition between baculovirus polyhedrin and p10 gene expression during infection of insect cells.
- Nuclear localization of the adenovirus DNA-binding protein: requirement for two signals and complementation during viral infection.
- Intracellular localization of viral polypeptides during simian virus 40 infection.
- Adenovirus type 2 nuclear RNA accumulating during productive infection.
- Vp1 affects intracellular localization of Vp3 polypeptide during simian virus 40 infection.