Figure 5.

LTA4H and BLT1 mediate phosphorylation of p27 at Thr187 affecting p27 ubiquitination. (A and B) A431 cells expressing control or LTA4H or BLT1 shRNA were transfected with the indicated constructs for 48 h and then incubated with MG132 (10 µM) for an additional 12 h. Whole cell lysates were co-immunoprecipitated with a p27 antibody followed by Western blotting with anti-HA or anti-p27. (C) A431 cells were transfected with the indicated constructs for 48 h and then incubated with MG132 (10 µM) for an additional 12 h. Whole cell lysates were co-immunoprecipitated with a p27 antibody followed by Western blotting with anti-HA or anti-p27. (D) A431 cells were infected with the indicated shRNAs for 48 h and then whole cell lysates were analyzed by Western blotting as indicated.