TONSL/TONSOKU binding to histone H3.1 is required for DNA repair.

TONSL/TONSOKU binding to histone H3.1 is essential for DNA repair, with mutations impairing this interaction disrupting repair functions in human cells.

• Why it matters: Understanding how TONSL/TSK interacts with histone H3.1 is crucial because these interactions are linked to genome stability and DNA repair, yet the detailed binding mechanisms and regulation were unclear.
• What they did: The study identified additional binding pockets in TSK/TONSL's TPR domain that recognize specific histone H3.1 modifications, including mono-methylated K4 and acetylated K27, and showed mutations in these pockets impair binding and repair.
• The result: Findings demonstrate that multiple PTMs regulate TSK/TONSL-histone H3.1 interactions, which are functionally important for DNA repair, highlighting potential targets for maintaining genome integrity.