Efficient targeted integration at leu1-32 and ura4-294 in Schizosaccharomyces pombe

Homologous integration into the fission yeast Schizosaccharomyces pombe has not been well characterized. In this study, we have examined integration of plasmids carrying the leu1⁺ and ura4⁺ genes into their chromosomal loci. Genomic DNA blot analysis demonstrated that the majority of transformants have one or more copies of the plasmid vector integrated via homologous recombination with a much smaller fraction of gene conversion to leu1⁺ or ura4⁺. Non-homologous recombination events were not observed for either gene. We describe the construction of generally useful leu1⁺ and ura4⁺ plasmids for targeted integration at the leu1-32 and ura4-294 loci of S. pombe.