title: Persistence and expression of Microplitis demolitor polydnavirus in Pseudoplusia includens.
abstract: Persistence and expression of Microplitis demolitor polydnavirus (MdPDV) was examined in parasitized and virus-injected Pseudoplusia includens larvae. Viral DNA persisted in P. includens larvae for 6 days, but no increase in the amount of viral DNA present was detected. Viral transcripts were observed in parasitized and virus-injected larvae 4 h post-parasitism and expression continued for 6 days. When specific host tissues were examined, more viral DNA and RNA was detected in haemocytes than in the gut, nervous system and fat body. 32P-labelled MdPDV DNA hybridized to approximately six different size classes of mRNAs on Northern blots of RNA from haemocytes of parasitized larvae. MdPDV transcription was first detected in haemocytes at 4 h post-parasitism and continued for 6 days. Similar transcripts were observed in haemocytes from larvae that had been injected with calyx fluid or MdPDV plus venom. First-strand cDNA probes of haemocyte-specific MdPDV transcripts hybridized to only certain MdPDV viral DNAs, suggesting that only part of the MdPDV genome is expressed in this host cell type.
authors.affiliation: Department of Entomology, University of Wisconsin, Madison 53706.
authors.forename: M R
authors.initials: MR
authors.lastname: Strand
authors.forename: D I
authors.initials: DI
authors.lastname: McKenzie
authors.forename: V
authors.initials: V
authors.lastname: Grassl
authors.forename: B A
authors.initials: BA
authors.lastname: Dover
authors.forename: J M
authors.initials: JM
authors.lastname: Aiken
mesh_terms: D000818:Animals; D016367:Baculoviridae / Q000302:isolation & purification*; D004279:DNA, Viral / Q000032:analysis; D005260:Female; D007814:Larva / Q000382:microbiology; D007915:Lepidoptera / Q000382:microbiology*; D012333:RNA, Messenger / Q000032:analysis; D012367:RNA, Viral / Q000032:analysis; D014863:Wasps / Q000382:microbiology*
chemical_list: D004279:DNA, Viral; D012333:RNA, Messenger; D012367:RNA, Viral