Figure S6. Cdt2 PIP box is important for its recruiting to DNA replication sites and its poly-ubiquitination activity in HEK293 cells.

(A) HEK293 cells or cells stable Cdt2^WT or Cdt2^PIP-3A were pre-extracted, fixed, and stained with PCNA and DYKDDDDK (FLAG) antibodies. (B) Poly-ubiquitination after UV irradiation. HEK293 and its stables expressing Cdt2^WT or Cdt2^PIP-3A were transfected with siCdt2 or control (siLuc). Three days later, cells were treated with MG132 (25 μM), and 10 min later irradiated with UV (20 J/m²). Cells were collected at the indicated time points, and used for Western blotting with indicated antibodies.