title: Microscopic investigation of AcMNPV infection in the Trichoplusia ni midgut.
abstract: Autographa californica multiple nucleopolyhedrovirus (AcMNPV) is the type species for the genus Alphabaculovirus in the family Baculoviridae. In nature, AcMNPV infection begins with ingestion of viral occlusion bodies (OBs) from which occlusion-derived viruses (ODV) are released to infect midgut cells. This study explored the early stages of Trichoplusia ni midgut infection using recombinant viruses expressing green fluorescent protein (GFP) and/or a VP39-mCherry fusion protein under the control of early and late promoters, respectively. Using a recombinant ie1:GFP virus, the anterior midgut region was identified as the predominant site for primary infection. Infection of midguts using the GFP-VP39mCherry-dual labelled recombinant virus revealed that active viral replication and cell-to-cell spread was required for the formation of infection foci and the subsequent spread to uninfected midgut cells and tracheoblasts. The spread of the infection from primary infected cells to secondary cells within the midgut was shown to be dependent upon the membrane fusion protein GP64.
authors: Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK S7N 0X2, Canada. Electronic address: afzal.javed@agr.gc.ca.
authors: Muhammad Afzal
authors: MA
authors: Javed
authors: Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK S7N 0X2, Canada. Electronic address: stephanie.harris@agr.gc.ca.
authors: Stephanie
authors: S
authors: Harris
authors: Summerland Research and Development Centre, Agriculture and Agri-Food Canada, Summerland, BC V0H 1Z0, Canada. Electronic address: les.willis@agr.gc.ca.
authors: Leslie G
authors: LG
authors: Willis
authors: Summerland Research and Development Centre, Agriculture and Agri-Food Canada, Summerland, BC V0H 1Z0, Canada. Electronic address: david.theilmann@agr.gc.ca.
authors: David A
authors: DA
authors: Theilmann
authors: London Research and Development Centre, Agriculture and Agri-Food Canada, London, ON N5V 4T3, Canada. Electronic address: cam.donly@agr.gc.ca.
authors: B Cameron
authors: BC
authors: Donly
authors: Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK S7N 0X2, Canada. Electronic address: martin.erlandson@agr.gc.ca.
authors: Martin A
authors: MA
authors: Erlandson
authors: Saskatoon Research and Development Centre, Agriculture and Agri-Food Canada, Saskatoon, SK S7N 0X2, Canada; Dept. of Food & Bio-Product Sciences, University of Saskatchewan, Saskatoon, SK S7N 4A8, Canada. Electronic address: dwayne.hegedus@agr.gc.ca.
authors: Dwayne D
authors: DD
authors: Hegedus
mesh_terms: D000818:Animals; D015153:Blotting, Western; D004064:Digestive System / Q000821:virology; D009036:Moths / Q000821:virology*; D017924:Nucleopolyhedroviruses / Q000378:metabolism*; D014764:Viral Proteins / Q000378:metabolism; D014774:Virulence; D014777:Virus Diseases / Q000662:veterinary*
chemical_list: D014764:Viral Proteins
keywords: AcMNPV; Baculovirus; Fluorescence microscopy; Midgut; Occlusion bodies; Oral infection; Pathogenesis; Trichoplusia ni