The Jak-STAT signaling pathway is required but not sufficient for the antiviral response of drosophila

Abstract

The response of drosophila to bacterial and fungal infections involves two signaling pathways, Toll and Imd, which both activate members of the transcription factor NF-kappaB family. Here we have studied the global transcriptional response of flies to infection with drosophila C virus. Viral infection induced a set of genes distinct from those regulated by the Toll or Imd pathways and triggered a signal transducer and activator of transcription (STAT) DNA-binding activity. Genetic experiments showed that the Jak kinase Hopscotch was involved in the control of the viral load in infected flies and was required but not sufficient for the induction of some virus-regulated genes. Our results indicate that in addition to Toll and Imd, a third, evolutionary conserved innate immunity pathway functions in drosophila and counters viral infection.

Genomic RNAi screening in Drosophila S2 cells: what have we learned about host–pathogen interactions?

“…Another pathway that has known signaling roles in innate immunity and in particular in anti-viral immunity is the JAK/Stat pathway [16][17][18]. Three large-scale RNAi screens have been performed, which probed the IMD signaling pathway in response to peptidoglycan [19][20][21] (Table 1).…”

Fruit Flies Like A (Rotten) Banana

“…21,22 Safia Deddouche (Jean-Luc Imler's lab, University of Strasbourg, in collaboration with several others) reported on the gene Vago, which is induced in the fat body after viral infection in a JAK-STAT independent manner, and suppresses proliferation of Drosophila C Virus (DCV). Deddouche and colleagues showed that the Flock House Virus protein B2, which interferes with RNAi through Dicer-2, suppresses induction of Vago.…”

Induction of host defence responses by Drosophila C virus

“…However, a number of viruses, including DCV, encode suppressors which inhibit this response (van Rij et al, 2006). Microarrays and proteomics have been used to identify genes and proteins that are upregulated in response to DCV infection in Drosophila (Dostert et al, 2005;Roxstrom-Lindquist et al, 2004;Sabatier et al, 2003). A number of genes have been found to be upregulated in response to DCV infection and one protein has been identified as being induced in the haemolymph of DCV-infected Drosophila (Sabatier et al, 2003).…”

“…A number of genes have been found to be upregulated in response to DCV infection and one protein has been identified as being induced in the haemolymph of DCV-infected Drosophila (Sabatier et al, 2003). Dostert et al (2005) identified 140 genes that were upregulated in adult Drosophila 24 and 48 h post injection with DCV. Two thirds of these genes were not upregulated in response to bacterial or fungal infections (Dostert et al, 2005).…”

“…Among the most upregulated of these virus-specific genes were CG12780, vir-1 and CG9080 (Dostert et al, 2005). Each of these three genes contain putative STATbinding sequences in their promoter regions and loss of function hop M38 /hop msvl mutant Drosophila supported the implied role of the Jak-STAT regulation of these genes, with the mutant hop flies having a greatly reduced ability to induce these genes (Dostert et al, 2005). In addition, vir-1 was not upregulated in response to bacterial or fungal infection or stresses including heat shock, cold shock, mechanical pressure, dehydration and UV irradiation (Dostert et al, 2005).…”