Pim-1 potentiates transcriptional activity of Runx1. (A) Jurkat TAg-cells were transfected with 4 μg of pM-CSF-R-Luc, 1 μg of pSV-β-gal, 4 μg of pEF-Runx1, 2 μg of pEF-Cbf β2, and indicated amounts of pLTR-pim-1. The steady-state levels of Pim-1 protein were measured from the same cell lysates by Western blotting with anti-Pim-1 antibody and equal loading was verified with anti-β-actin antibody. (B) Jurkat TAg-cells were transfected with same reporter constructs as in Figure A together with wild-type or mutant pSV-pim-1 constructs. (C) Jurkat TAg-cells were transfected with 3 μg of pG5-Luc, 1 μg of pSV-β-gal, 3 μg of GAL4 fusion proteins and 2 μg of pEF-Cbf β2 together with indicated amounts of pLTR-pim-1. Shown are relative luciferase activities normalized against β-galactosidase activities and statistically analysed by Student's t-test (*, p ≤ 0.05; **, p ≤ 0.01).