L arginine 13c6 and l lysine 2h4

U2OS and HEK293T cells were obtained from ATCC and cultured in d-MEM medium supplemented with 10% fetal bovine serum, l-glutamine, penicillin, and streptomycin. Cells were routinely tested for mycoplasma infection with a PCR-based method. For SILAC labeling, cells were cultured in media containing either l-arginine and l-lysine, l-arginine [13C6] and l-lysine [2H4] or l-arginine [13C615N4] and l-lysine [13C6-15N2] (Cambridge Isotope Laboratories) as described previously (62 (link)). All cells were cultured at 37°C in a humidified incubator containing 5% CO₂.

U2OS, HeLa and HEK293T cells were maintained in DMEM containing 10% fetal bovine serum, L‐glutamine (2 mM), penicillin (100 U/ml), and streptomycin (100 µg/ml) (Thermo Fisher Scientific). U2OS Flp-In T-REx cell lines were maintained in DMEM containing 10% fetal bovine serum, L‐glutamine, penicillin, streptomycin and blasticidin (5 µg/ml) (Invivogen). All cell lines were cultured in humidified incubators at 37 °C with 5% CO₂. Treatments were performed with hydroxyurea (4 mM, Merck), the MRE11 inhibitor mirin (25 µM, Merck) or the DNA2-specific inhibitor C5 (25 µM, AOBIOUS) for 5 h. For SILAC labeling, HeLa cells were cultured for at least 5 passages in SILAC DMEM (Invitrogen) supplemented with dialyzed FBS (Invitrogen) and containing either L-arginine and L-lysine (Merck) or L-arginine [13C6] and L-lysine [2H4] (Cambridge Isotope Laboratories).

U2OS (derived from bone tissue from 15-year old female osteosarcoma patient) and HCT116 (derived from the colon of adult male) cells were obtained from ATCC and cultured in D-MEM medium supplemented with 10% fetal bovine serum, L-glutamine, penicillin and streptomycin. Cells were routinely tested for mycoplasma infection with a PCR-based method. For SILAC labeling, cells were cultured in media containing either L-arginine and L-lysine, L-arginine [13C6] and L-lysine [2H4] or L-arginine [13C6-15N4] and L-lysine [13C6-15N2] (Cambridge Isotope Laboratories) as described previously (Ong et al., 2002 (link)). All cells were cultured at 37°C in a humidified incubator containing 5% CO2.