# Alpha-Glucosidase of Manduca sexta Is an Entry Factor for Daphnis nerii Cypovirus-23

## TL;DR

A study identifies an enzyme in Manduca sexta that helps a virus infect its host, offering insights into viral entry mechanisms.

## Contribution

The study identifies MsAGL as a novel entry factor for DnCPV-23 virus in Manduca sexta cells.

## Key findings

- VP3 mediates DnCPV-23 binding to host membrane vesicles.
- MsAGL interacts with VP3 and influences virus entry into host cells.
- MsAGL inhibits DnCPV-23 infection in M. sexta cells and D. nerii larvae.

## Abstract

Daphnis nerii can severely damage pine forests worldwide. Daphnis nerii cypovirus-23 (DnCPV-23) is an important viral pathogen for controlling D. nerii. However, the mechanism underlying DnCPV-23 cell entry has not been elucidated. In this study, we determined that VP3 mediates the binding of DnCPV-23 to host brush border membrane vesicles. Far-Western blotting and mass spectrometry results revealed that a Manduca sexta alpha-glucosidase (MsAGL) can interact with VP3. The interaction between MsAGL and VP3 was verified by co-immunoprecipitation and glutathione S-transferase pull-down assays. Notably, MsAGL influenced DnCPV-23 entry into host cells, including attachment and the subsequent internalization of the virus. Furthermore, MsAGL inhibited DnCPV-23 infections of M. sexta cells and D. nerii larvae. In summary, we confirmed that VP3 of DnCPV-23 mediates cell entry, while also identifying MsAGL as an entry factor for DnCPV-23. The study findings provide useful insights relevant for further elucidating the cell entry mechanisms of cypoviruses.