Isolation of Trypanosoma cruzi DNA fragments which function as ARS elements in Saccharomyces cerevisiae

Genomic banks from Trypanosoma cruzi total cell DNA and kinetoplast DNA were constructed in a bacterial plasmid carrying the yeast URA3 gene marker. This vector is by itself unable to be maintained in Saccharomyces cerevisiae since it can neither replicate as an extrachromosomal element, nor readily integrate into the chromosome of ura3-52 yeast hosts. Using this system, we isolated sequences from nuclear and kinetoplast DNA of T. cruzi which enabled the vector to replicate autonomously in S. cerevisiae. The cloned DNA fragments fit the description of ARS sequences previously isolated from other organisms.