Deletion of RAD52 in Saccharomyces cerevisiae severely decreases frequencies of Agrobacterium genetic transformation mediated by either an integrative or a replicating binary vector

Agrobacterium tumefaciens is capable to transfer genes across kingdoms. It can genetically transform not only plant cells, but also many other bacterial, algal, fungal, animal and human cells. This depends on the interactions among a variety of both Agrobacterium and host genes. Inside the host cell, RAD52 which is involved in DNA repair is a key gene determining integration of T-DNA by homologous recombination. Here, using Saccharomyces cerevisiae haploid strains BY4741 and BY4742, a rad52 diploid deletion strain was constructed in yeast BY4743 background. This model organism was employed to show that RAD52 deletion severely decreases frequencies of Agrobacterium genetic transformation mediated by either an integrative TDNA or a circular non-integrative T-DNA. Indeed, the frequencies of such Agrobacterium-mediated transformation (AMT) decreased by ca. 25-fold, compared to wild type BY4743. Hence, host RAD52 deletion might affect AMT by a mechanism which differs from its only involvement in DNA repair in yeast.