Dual mutations in the Autographa californica nucleopolyhedrovirus FP-25 and p35 genes result in plasma-membrane blebbing in Trichoplusia ni cells

• Published in: Journal of general virology 2006-03, Vol.87 (3), p.531-536
• Main Authors: Kelly, Barbara J, King, Linda A, Possee, Robert D, Chapple, Susan D. J
• Format: Article
• Language: English
• Subjects: Animals; Autographa californica; Base Sequence; Biological and medical sciences; Caspase 3; Caspases - metabolism; Cell Line; Cell Membrane - pathology; Fundamental and applied biological sciences. Psychology; Genes, Viral - genetics; Microbiology; Miscellaneous; Molecular Sequence Data; Moths; Mutation; Nuclear polyhedrosis virus; Nucleocapsid Proteins - genetics; Nucleopolyhedrovirus - genetics; Nucleopolyhedrovirus - physiology; Spodoptera frugiperda; Trichoplusia ni; Viral Proteins - genetics; Virology; Virus Replication
• ISSN: 0022-1317; 1465-2099
• DOI: 10.1099/vir.0.81312-0

1 Centre for Ecology and Hydrology Oxford, Mansfield Road, Oxford OX1 3SR, UK 2 School of Biological and Molecular Sciences, Oxford Brookes University, The Headington Campus, Oxford OX3 0BP, UK Correspondence Robert D. Possee rdpo{at}ceh.ac.uk Spodoptera frugiperda cells infected with Autographa californica nucleopolyhedrovirus (AcMNPV) lacking a functional anti-apoptotic p35 protein undergo apoptosis. However, such mutants replicate normally in Trichoplusia ni (TN-368) cells. An AcMNPV plaque isolate (AcdefrT) was identified during propagation of a virus deficient in p35 in TN-368 cells. This virus exhibited enhanced budded-particle formation in TN-368 cells, but was partially defective for polyhedra production in the same cells. Virus replication in AcdefrT-infected TN-368 cells was accompanied by extensive plasma-membrane blebbing and caspase activation late in infection, both features of apoptosis. Rescue of the p35 locus of AcdefrT continued to result in a reduction in polyhedra and increase in budded virus production in TN-368 cells, but no plasma-membrane blebbing was observed. The mutation was mapped to the FP-25 gene locus. This gene mutation combined with the non-functional p35 was found to be responsible for the cell-blebbing effect observed in AcdefrT-infected TN-368 cells. Present address: Department of Microbiology, The Moyne Institute of Preventative Medicine, Trinity College, Dublin 2, Ireland. Present address: The Wellcome Trust Sanger Institute, Wellcome Trust Genome Campus, Hinxton, Cambridge CB10 1SA, UK.