Extensive alteration of fungal gene transcript accumulation and elevation of G-protein-regulated cAMP levels by a virulence-attenuating hypovirus.
AUTOR(ES)
Chen, B
RESUMO
Persistent infection of the chestnut blight fungus Cryphonectria parasitica with the prototypic hypovirus CHVI-713 results in attenuation of fungal virulence (hypo-virulence) and reduced accumulation of the GTP-binding (G) protein a subunit CPG-1. Transgenic cosuppression of CPG-1 accumulation in the absence of virus infection also confers hypovirulence. We now report the use of mRNA differential display to examine the extent to which virus infection alters fungal gene transcript accumulation and to assess the degree to which modification of CPG-1 signal transduction contributes to this alteration. More than 400 PCR products were identified that either increased (296 products) or decreased (127 products) in abundance as a result of virus infection. Significantly, 65% of these products exhibited similar changes as a result of CPG-1 cosuppression in the absence of virus infection. We also report that both virus infection and CPG-1 cosuppression elevate cAMP levels 3- to 5-fold. Additionally, it was possible to mimic the effect of virus infection and CPG-1 cosuppression on transcript accumulation for representative fungal genes by drug-induced elevation of cAMP levels. These results strengthen and extend previous indications that hypovirus infection causes a significant and persistent alteration of fungal gene expression/transcript accumulation. They further show that this alteration is primarily mediated through modification of the CPG-1 signaling pathway and suggest that, similar to mammalian Gi alpha subunits, CPG-1 functions as a negative modulator of adenylyl cyclase. Finally, these results suggest a role for G-protein-regulated cAMP accumulation in hypovirus-mediated alteration of fungal gene expression.
ACESSO AO ARTIGO
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=38863Documentos Relacionados
- Regulatory pathways governing modulation of fungal gene expression by a virulence-attenuating mycovirus.
- Cryptococcus neoformans mating and virulence are regulated by the G-protein α subunit GPA1 and cAMP
- Use of cDNA Microarrays To Monitor Transcriptional Responses of the Chestnut Blight Fungus Cryphonectria parasitica to Infection by Virulence-Attenuating Hypoviruses
- Inhibition of Membrane Tubule Formation and Trafficking by Isotetrandrine, an Antagonist of G-protein-regulated Phospholipase A2 Enzymes
- Identification of a novel cytosolic poly-phosphoinositide-specific phospholipase C (PLC-86) as the major G-protein-regulated enzyme.