Ectopic AP-1 subunits induce Blimp1 expression.

<p>(A) H441 cells, growing in 6-well plates, were transfected with 1 µg of vectors expressing the indicated AP-1 subunits or EV DNA (see bottom) to make a 2 µg total. Upper panel. After 48 h, RNA was isolated and subjected to Q-PCR. The levels of <i>BLIMP1</i> mRNA normalized to <i>GAPDH</i> mRNA are presented as mean ± SD of three independent experiments. Middle and lower panels. WCE were isolated and subjected to immunoblotting (IB) for Blimp1 (Middle panels), and for c-Jun, Fra-1, Fra-2, c-Fos and β-actin (Lower panels). (L exp., longer exposure; S exp., shorter exposure). Blimp1 levels, normalized to β-actin, were determined as in <a href="http://www.plosone.org/article/info:doi/10.1371/journal.pone.0033287#pone-0033287-g001" target="_blank">Fig. 1C</a> and average values from two independent experiments presented relative to EV DNA, set to 1.0. (B) H441 cells were transiently transfected, in triplicate, with 0.3 µg of <i>Blimp1</i>-Luc, 0.3 µg of MSV-β-gal, and vectors expressing the indicated AP-1 subunits (0.15 µg each) and EV DNA to a total of 1.0 µg DNA. Normalized values of <i>Blimp1</i> promoter activity are presented as the mean ± SEM from two experiments (EV DNA set to 1.0).