Thiirane linkers directed histone H2A diubiquitination suggests plasticity in 53BP1 recognition

Polyubiquitination with diverse linkages on histones provides another layer of accuracy and complexity for epigentic regulation, which is rarely studied. Herein, K27 or K48-diubiquitin modified H2A analogues were chemically synthesized through thiirane linkers. These permitted in vitro binding studies that suggested the plasticity of ubqiutin chains in 53BP1 recognition.