Toxoneuron nigriceps polydnavirus encodes a putative aspartyl protease highly expressed in parasitized host larvae
Article first published online: 22 JAN 2003
Insect Molecular Biology
Volume 12, Issue 1, pages 9–17, February 2003
How to Cite
Falabella, P., Varricchio, P., Gigliotti, S., Tranfaglia, A., Pennacchio, F. and Malva, C. (2003), Toxoneuron nigriceps polydnavirus encodes a putative aspartyl protease highly expressed in parasitized host larvae. Insect Molecular Biology, 12: 9–17. doi: 10.1046/j.1365-2583.2003.00382.x
- Issue published online: 22 JAN 2003
- Article first published online: 22 JAN 2003
- Received 12 March 2002; accepted after revision 11 September 2002.
- gene expression;
- host regulation
Toxoneuron nigriceps (Viereck) (Hymenoptera: Braconidae) is an endophagous parasitoid of larval stages of the tobacco budworm, Heliothis virescens (F.) (Lepidoptera: Noctuidae). This parasitoid is associated with a polydnavirus (TnBV), injected at oviposition along with the egg, and involved in the disruption of host immune reaction and endocrine balance. This paper reports the molecular characterization of TnBV2, one of the most abundant genes in the TnBV genome. TnBV2 expression produces a mature 0.6 kb transcript in fat body, prothoracic glands and haemocytes, as early as 6 h after parasitoid oviposition. Only in haemocytes a specific longer transcript of 2.5 kb is found 24 h after parasitization. The putative translation product of TnBV2 contains a retroviral type aspartyl protease domain. The possible origin and functional role of this TnBV gene are discussed.