SAGA complex mediates the transcriptional up-regulation of antiviral RNA silencing

This is the authors' abstract. We don't add key points for this paper.

Significance RNAi-mediated antiviral defense is well conserved in eukaryotic organisms. Although several RNAi key genes are transcriptionally up-regulated upon virus infection in many hosts, little is known about their induction mechanism. Here, we developed a screening method for identification of the genes mediating robust transcriptional up-regulation upon infection by RNA viruses of the dicer-like 2 ( dcl2 ) gene of an ascomycetous phytopathogen, chestnut blight fungus. We show that two enzymatic activities of histone acetyltransferase and histone deubiquitinase of the universally conserved SAGA (Spt–Ada–Gcn5 acetyltransferase) complex differentially regulate the transcriptional induction of two main antiviral RNA silencing components, dcl2 and argonaute-like 2 ( agl2 ). A virus-specific pattern requirement of AGL2 and DCL2 as positive feedback players for this transcriptional induction is also noted.