9404852 Russell The long-term objective of this project is to understand the genetic control of the establishment of infection and the in vivo replication of yeast double-stranded RNA viruses. The research will define the important cis-acting viral sequences and the trans-acting host yeast genes necessary and sufficient for establishing an infection and for in vivo replication of the L-A and M1 double-stranded RNA viruses of yeast. Replicon systems for analyzing the molecular details of viral infection and replication will be developed. Properties of successful replicons will be compared with the properties of natural L-A and M1 viruses. The 5' and 3' sequence requirements for and sequence context effects on infection replication and translation will be identified. %%% The research will contribute to our knowledge of the genetics and molecular biology of the viral life cycle, and of viral/host interactions in yeast. The genetic tractability of yeast makes it possible to define interactions between host genes and viral functions. By contrast, in mammalian systems, the difficulty of doing genetics makes such detailed studies of host-virus interactions very challenging if not impossible. The knowledge obtained in this research may be generalized to other viral systems, including those of agricultural and environmental significance; in particular, newly-identified yeast genes involved specifically in the virus life cycle will facilitate searches for similar genes in other systems. ***
