(a)
(b)
(c)
Figure 5: PU.1-dependent regulation of ATG3, ATG4D, and ATG5 during ATRA-mediated differentiation of NB4 cells. (a) ATG3, ATG4D, and ATG5 mRNA expression levels were quantified in NB4 shPU.1 cells treated with ATRA for 4 days. (b) NB4 cells, transduced with an inducible PU-1-ER expressing vector, were treated with 4-OHT to induce PU.1 translocation to the nucleus. ATG3, ATG4D, and ATG5 mRNA expression levels were quantified as in (a). (c) Schematic representation of ATG3, ATG4D, and ATG5 proximal promoter regions. Putative PU.1 binding sites in these promoter regions are indicated as black circles. In vivo binding of PU.1 to the indicated PU.1 binding sites was shown by ChIP in NB4 cells using antibodies against PU.1. Antibodies against acetyl-histone H3 and IgG are used as positive and negative controls, respectively. GAPDH amplification was shown as a negative control for the different pull-downs. Mann–Whitney U test, .