Fig. 1.

Damage-induced degradation of Sp1 results in increased p21 expression. a, b hTert-BJ1 cells were depleted of Sp1 using CRIPSR/Cas9 and transduced with lentivirus expressing Flag-tagged Sp1^WT, Flag-tagged Sp1-30N^WT, or empty-vector (Sp1^−/−) (Supplemental Fig. 1a). Cells were treated with 200 μM H₂O₂ for 2 h, which was then replaced with fresh media for a total of 24 h. Lysates were collected at indicated time points past H₂O₂ removal and used for Western blot analysis of protein levels. Sp1 antibody does not detect Flag-Sp1-30 N. b Cells described in a were also treated with 10 μM MG132 for entire length of experiment