plasmid-based BIR screen in S. cerevisiae

We used a plamsid-based assay to identify novel S. cerevisiae mutants with abnormal Break Induced Replication (BIR) efficiencies. We pooled the ca. 5000 yeast deletion mutants from the systematic deletion library and compared the relative tranformation efficiencies of a circular versus linear truncated minichromosome using tag arrays. Our main result is the identification of Fun30 as a novel chromatin remodelr facilitating DNA end resection. A pool of ca. 5000 yeast deletion mutants from the systematic deletion library was transformed with a circular minichromosome on one hand, and with a linear truncated minichromosome on the other hand. Transformants were recovered, DNA was extracted and the systematic tags were PCR amplified with complementary dyes for the two transformations. Amplified tags were mixed and hybridized on a tag array. The overall experiment was done twice.