Deciphering the chromatin landscape induced around DNA double strand breaks

Targeting Protein for Xenopus Kinesin-like Protein 2 (TPX2) Regulates γ-Histone 2AX (γ-H2AX) Levels upon Ionizing Radiation

“…Furthermore, TPX2 also formed foci positive for ␥-H2AX in a system that introduces AsiSI-generated DNA double strand breaks (56) (Fig. 3C).…”

DNA double strand break repair pathway choice: a chromatin based decision?

“…Using a human cell line (called DIvA for DSB Inducible via AsiSI) in which multiple annotated DSBs can be induced in a controlled manner using a restriction enzyme, 20,21 we established that distinct DSBs across the genome are not necessarily repaired by the same pathway. 22 By ChIP-seq mapping of XRCC4 (a NHEJ component) and RAD51 (involved in HR), we identified an HR-prone subset of AsiSI-induced DSBs that, during the G2 cell cycle phase, is able to recruit RAD51, undergo resection and rely on RAD51 for efficient repair, and a non-HR prone subset, that even in G2 is unable to recruit RAD51 and require XRCC4 for efficient end joining.…”

Dynamics of DNA damage response proteins at DNA breaks: a focus on protein modifications

“…The generation of sequence-specific DSBs by selected endonucleases was pioneered with yeast homothallic (HO) endonuclease (Sugawara and Haber 2006), translated into mammalian cells by using homing endonucleases such as I-SceI (Jasin 1996) and I-PpoI (Berkovich et al 2008), and more recently developed into genome-wide formats by combining expression of the restriction enzyme AsiSI with microarray hybridization and high-throughput sequencing Massip et al 2010). Furthermore, generation of DSBs by the targeting of a nuclease to a defined locus in the genome can be attained by fusing its nuclease domain to a zinc finger protein or a Lac repressor, as was done recently with the FokI enzyme (Urnov et al 2005;Shanbhag et al 2010).…”