This proposal is for the continuation of studies on the unusual bacteriophage 06 of Pseudomonas phaseolicola. The phage is unique because it contains a lipid envelope and a tripartite segmented dsRNA genome. These features along with an associated RNA polymerase, genome size comparable to some oncogenic viruses, and similarities in replication to the dsRNA reoviruses suggest a number of analogies between 06 and some mammalian viruses. These similarities suggest that 06 may serve as a useful model system for some aspects of oncogenic molecular biology. We will characterize the phage proteins coded by the phage genome and assign them to specific dsRNA segments by both biochemical and genetic procedures. Different types of mutants will be isolated and examined by complementation tests to determine phage function and recombination analysis to determine linkage. Assignment of function to specific gene sites will be made from in vivo and in vitro analysis of products synthesized under permissive and non-permissive conditions. Also we will analyze the nature of the early RNA synthesis of wild type and mutant phage infected cells. We will examine carrier state cells of the host to determine how the genetic information of 06 is maintained and determine if 06 can be induced or the cells "cured" of 06. In the latter experiments, carcinogens and other agents which are known to induce c-type particles in mammalian systems will be tested. Finally, we will investigate the mechanism(s) by which plants inactivate bacteriophages.