The Dictyostelium slime molds have an extensive array of nuclear plasmids. Since our knowledge of eukaryotic plasmids of this type is extremely limited, characterization of these plasmids will be informative. It is proposed to provide an analysis of the genes and sequences on Ddp1 that are necessary for stable high copy number maintenance of plasmid DNA during nonselective growth conditions. The data will allow comparison of Ddp1 to plasmids and viral genomes from other species, thereby increasing our knowledge of what it takes to be a eukaryotic plasmid. This information is essential for the construction and application of stably- maintained transformation vectors based on plasmids.
