Nucleosome Dynamics Around a DNA Double Stranded Break During Repair by Gene Conversion.

• DOI: 10.1096/fasebj.29.1_supplement.709.8
• Publication Date: 2021-06-21T18:40:16Z
• Authors: Michael Tsabar; Wade Hicks; James Haber
• Keywords: 0301 basic medicine; 0303 health sciences; 03 medical and health sciences

In eukaryotes, double‐stranded break repair (DSB) takes place in the context of chromatin. Saccharomyces cerevisiae mating type ( MAT ) switching provides an opportunity to investigate nucleosome dynamics around a well‐characterized DSB. is initiated by synchronous induction DSB HO endonuclease at locus following which ends are resected and Rad51 recombinase loaded on 3‐ended single strand. facilitates strand invasion with homologous donor sequence, required for initiation new DNA synthesis resulting repair. A hurdle studying positioning has been weak relative heterochromatic donors HML HMR . To address this we designed novel system inserted Xenopus laevis 5S sequence adjacent locus. Using have, first time, monitored loss chromatin protection resection end re‐establishment structure We show that lost resection‐dependent manner. Further, reestablished but not level seen prior This reestablishment depends passage through cell cycle. complete after several cycles, suggesting there mechanistic difference between repair‐dependent replication‐dependent positioning.