抄録：The Basidiomycota is the second largest division of the fungal kingdom after the Ascomycota. Basidiomycota biology has been much less explored than Ascomycota, partly because there are no major Basidiomycota model organisms. In this study, with the aim of establishing a Basidiomycota budding yeast, Naganishia liquefaciens, as a model organism, I have developed genetic tools that enable efficient gene targeting. The gene targeting method combined with a CRISPR-Cas9 system, routinely achieves ~80% gene targeting efficiency. I further explored the genetic requirement for this homologous recombination (HR)-mediated gene targeting. The absence of Ku70, a major component of the non-homologous end-joining (NHEJ) pathway of DNA double-strand break repair, almost completely eliminated inaccurate integration events. Gene targeting with short homology (80 bp) requires almost exclusively Rad52, an essential component of HR in the Ascomycota yeasts Saccharomyces cerevisiae and Schizosaccharomyces pombe, while a rad52 deletion mutant retains a relatively high efficiency of gene targeting with long homology arms (1 kb). By contrast, the RecA homolog Rad51, which performs homology search and strand exchange in HR, plays a relatively minor role in gene targeting, regardless of the homology length (80 bp or 1 kb). Interestingly, the absence of both Rad51 and Rad52 completely eliminated gene targeting even with the long homology arms. Unlike Ascomycota yeasts, the absence of Rad52 in N. liquefaciens does not cause DNA damage sensitivity. These observations lead to the identification of human breast and ovarian tumor suppressor protein BRCA2 homolog (Brh2), which is lacking in S. cerevisiae and S. pombe, in N. liquefaciens. The brh2 mutants and brh2 rad51 double mutants were found to be sensitive to DNA damage to the same extent as the rad51 mutants, indicating recombinational repair system in N. liquefaciens is BRCA2 dependent.

日時：2022年2月10日（木）16：00 〜

事前登録：https://zoom.us/webinar/register/WN_8wyxNebeSB2DkQqEM0-JUA

連絡先：斉藤典子（内線5474）

本セミナーは完全オンラインです。事前登録をお願いします。