CHEK1 and Fanconi anemia: Consistently, we observed that transcriptional levels of DDR downstream proteins in zeocin-treated resting T cells, including CHK1, CHK2 and many factors in non-homologous end joining (NHEJ), homologous recombination (HR) and Fanconi Anaemia pathway, were much lower than that in zeocin-treated stimulated T cells (Supplementary Figure 5).