One characteristic of all positive-strand RNA viruses is the necessity to assemble viral RNA replication complexes on host intracellular membranes, a process whose molecular details are poorly understood. To study viral replication complex assembly we use the established model system, Flock House virus (FHV), which assembles its replication complexes on the mitochondrial outer membrane. The FHV RNA-dependent RNA polymerase, protein A, is the only viral protein necessary for genome replication in the budding yeast Saccharomyces cerevisiae. To examine the host components involved in protein A-membrane interactions, an initial step of FHV RNA replication complex assembly, we established an in vitro protein A membrane association assay. Protein A translated in vitro rapidly and specifically associated with mitochondria isolated from yeast, insect, and mammalian cells. This process was temperature-dependent but independent of protease-sensitive mitochondrial outer membrane components or the host mitochondrial import machinery. Furthermore, lipid binding studies revealed that protein A preferentially bound to specific anionic phospholipids, in particular the mitochondrial-specific phospholipid cardiolipin. These studies implicate membrane phospholipids as important host determinants for FHV RNA polymerase membrane association and provide evidence for the involvement of host phospholipids in positive-strand RNA virus membrane-specific targeting.
|Evidence ID||Analyze ID||Interactor||Interactor Systematic Name||Interactor||Interactor Systematic Name||Type||Assay||Annotation||Action||Modification||Phenotype||Source||Reference||Note|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Gene Ontology Term||Gene Ontology Term ID||Qualifier||Aspect||Method||Evidence||Source||Assigned On||Reference||Annotation Extension|
|Evidence ID||Analyze ID||Gene||Gene Systematic Name||Phenotype||Experiment Type||Experiment Type Category||Mutant Information||Strain Background||Chemical||Details||Reference|
|Evidence ID||Analyze ID||Regulator||Regulator Systematic Name||Target||Target Systematic Name||Experiment||Conditions||Strain||Source||Reference|