Figure 4.

MCL-1 ubiquitin ligase MULE was stabilized by KRIBB11. (A) The effect of MULE depletion on MCL-1 was examined by transfection of specific siRNA (100 nM) for 48 h and subsequent Western blotting (upper). The relative levels of MCL-1 after depletion of CHIP or MULE were shown by densitometry analysis (lower). (B) MULE depletion retarded the KRIBB11-induced MCL-1 reduction, which was evaluated by Western blotting. (C,D). MULE levels after KRIBB11 treatment were determined by Western blotting (C) and qRT PCR analysis (D). (E) Cycloheximide (50 μg/mL) was treated with KRIBB11 (2.5 μM), and the kinetics of MULE expression was compared with cycloheximide only group by Western blotting (left). The quantitation of MULE was performed with densitometry (right). Data are mean ± SE of three independent experiments. * p < 0.05 vs. control values.