Research Seminar: Chromatin and Chromosome dynamics during DNA Double Strand break repair

Dr. Gaëlle Legube, Chromatin and DNA Repair Group, Integrative Biology Centre, University of Toulouse, France

Tuesday 20th November, 1.00 p.m., Stacey Lecture Theatre 1

 

Double-Strand Breaks (DSB) are highly detrimental DNA lesions that can cause cancer-driving mutations or translocations. Non-Homologous End Joining and Homologous Recombination represent the two main repair pathways operating in the context of chromatin to ensure genome stability. Despites extensive efforts, our knowledge of DSB-induced chromatin still remains fragmentary. Using a cell line, called DIvA (for DSB Inducible via AsiSI), where multiples breaks can be induced at annotated positions throughout the human genome, combined with ChIP-seq, we try to provide a comprehensive picture of the chromatin landscape set up at DSBs and identify specific chromatin events occurring upon NHEJ and HR. Moreover, using ChIP-seq against HR and NHEJ proteins, as well as Capture Hi-C, we have also reported that when damaged, transcriptionally active units adopt a very peculiar behavior, being repaired by HR in G2 and left unrepaired and clustered in G1, pointing toward a potential “transcription coupled DSB repair” pathway.