ALTERNATIVE mRNA SPLICE VARIANTS IN DROSOPHILA DL2 CELLS FOLLOWING FLOCK HOUSE VIRUS INFECTION

摘要

There is a paucity of information regarding the responses of the insect immune system to viral infection. In other metazoan cells and tissues mRNA splicing variants are frequently associated with viral infection. Here we analyzed transcripts of theDNA repair gene 8-oxoguanine DNA glycosylase generated prior to, and post, infection of Drosophila melanogaster macrophage-like DL-2 cells by Flock House Virus (FHV). In mock-infected controls we observed that 2% of the transcripts were incompletely processed, maintaining some but not all introns. Eight hours post-FHV infection of the DL-2 cells, we observed a seven fold increase in the frequency of immature Ogg1 transcripts. Moreover, there was a change in the introns retained in the transcripts observed compared with mock-infected controls, including completely unspliced transcripts. Surprisingly, the frequency of immature transcripts was reduced to control levels by 12 hours post-inoculation and remained relatively low tip to 48 hrs. These results support the conclusion that viral infection may be accompanied by a host-mediated partial inhibition of mRNA splicing factors. This phenomenon has the potential to generate novel splice variants that are neither directly useful to the host nor the infecting virus but have the potential to degrade the transmission of genetic information. To our knowledge this the first report that viral infection may Published November 2008