HMCES Functions in the Alternative End-Joining Pathway of the DNA DSB Repair during Class Switch Recombination in B Cells (Molecular Cell)

HMCES (5hmC binding, embryonic stem cell-specific protein), originally found to bind 5-hydroxymethylcytosine (5hmC), was recently reported to covalently crosslink to DNA at abasic sites. Shukla et al. show that HMCES specifically enables DNA double-strand break repair through the microhomology-mediated alternative-end-joining (Alt-EJ) pathway during class switch recombination (CSR) in B cells.