Figure 5.

Two potential mechanisms to prevent DSB mis-repair and loss of DNA fragments at clustered DSBs. (A) Chromatin consists of DNA wrapped around nucleosomes that are highly compacted into 30 nm fibers and higher order structures. (B) Schematic of chromatin shown as a “scaffold” around DNA. (C,D) Radiation induces clustered DSBs and short DNA fragments that are prevented from mis-rejoining and/or loss by tethering factors such as DNA-PK, and by the chromatin scaffold which may act like a “splint” or “sausage skin” to prevent loss of short DNA fragments.