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Published on: November 4, 2014
Surface display of AcMNPV occlusion-derived P74 does not enhance oral infectivity of budded viruses
Victoria Alfonso1, María Gabriela López, Elisa Carrillo
1Instituto de Biotecnología, CICVyA, INTA-Castelar, Hurlingham, Argentina. valfonso@cnia.inta.gov.ar
Abstract:
Baculovirus occlusion-derived viruses (ODVs) and budded viruses (BVs) are morphologically and functionally distinct. ODVs are responsible for primary infection in insect hosts because of their high per os infectivity. On the contrary, BVs poorly infect endothelial gut cells, but propagate the infection in the tissues of insects with a high efficiency. P74 is one of the most important proteins from ODVs, and it participates in the attachment of this viral phenotype to endothelial cells in the midgut. We evaluated the possibility of pseudotyping BVs of Autographa californica multiple nucleopolyhedrovirus with two versions of P74 and its effect on their oral infectivity. Both recombinant BVs contained P74 and replicated similarly to wild-type viruses. Nevertheless, the presence of P74 on the BV's surface does not enhance the oral infectivity of this phenotype, suggesting that the presence of P74 in the membrane of budded virions interferes with their mechanism of infecting midgut cells.
Insights
Pseudotyping budded viruses (BVs) with the P74 protein did not enhance their oral infectivity. This suggests P74 on BV surfaces may hinder midgut cell infection, despite its role in occlusion-derived virus (ODV) entry.
Area of Science:
- Virology
- Molecular Biology
- Insect Pathology
Background:
- Baculovirus occlusion-derived viruses (ODVs) are crucial for primary insect infection due to high oral infectivity.
- Budded viruses (BVs) efficiently propagate infections within insect tissues but have low oral infectivity.
- The P74 protein is essential for ODV attachment to insect midgut endothelial cells.
Purpose of the Study:
- To investigate the effect of pseudotyping Autographa californica multiple nucleopolyhedrovirus (AcMNPV) BVs with P74 on their oral infectivity.
- To determine if incorporating P74 into the BV envelope enhances infection of midgut cells.
Main Methods:
- Generation of recombinant AcMNPV BVs expressing two versions of the P74 protein.
- Comparative analysis of viral replication and oral infectivity between recombinant BVs and wild-type viruses.
- Evaluation of P74 presence on BV surface and its impact on infection mechanisms.
Main Results:
- Recombinant BVs expressing P74 replicated similarly to wild-type AcMNPV.
- The presence of P74 on the BV surface did not increase their oral infectivity.
- P74 incorporation into BVs did not improve infection of insect midgut cells.
Conclusions:
- Pseudotyping AcMNPV BVs with P74 does not enhance their oral infectivity.
- The P74 protein on the BV surface appears to interfere with the mechanism of midgut cell infection.
- This finding highlights distinct functional roles of P74 in ODV and BV infection pathways.
