Figure 6. BCL10 promotes RNF8/RNF168-mediated ubiquitination in response to DNA damage. (A) Inhibition of BCL10 expression reduced DNA damage-induced FK2 foci. BCL10 or mock-depleted HeLa cells were treated with or without etoposide 1 h before fixed with 4% paraformaldehyde and subsequently immunostained with an anti-FK2 antibody. (B) Depletion of BCL10 compromised γ-H2AX mono- and poly-ubiquitination after DNA damage. BCL10-depleted or mock-depleted 293T cells were co-transfected with FLAG-H2AX and HA-Ub. Transfectants were treated 48 h after transfection with etoposide or DMSO for 1 h, and total cell lysates were extracted for immunoprecipitation with an anti-FLAG antibody and immunoblotting with antibodies as indicated. The efficiency of BCL10 knockdown was determined by immunoblotting with antibodies as indicated. Mono-Ub, mono-ubiquitinated H2AX; di-Ub: di-ubiquitinated H2AX.