Figure 2.

PMA induction of TAK activity in U1 and U937 promonocytic cell lines. U1 and U937 cells were incubated in medium alone or medium containing PMA for 48 hr. (A) Kinase assays for TAK, CDK7, and CDK2 activities were performed as described in Fig. 1. (B) Amount of p24 in culture supernatants was measured by ELISA.