Nrf1b expression is widely distributed.

<p>Nrf1a and Nrf1b mRNA expression patterns were analyzed by RT-PCR in various cell lines (<b>A</b>) and mouse tissues (<b>B</b>)<b>.</b> Nrf1a and Nrf1b cDNA was amplified by PCR for 30 cycles and 18S was amplified for 20 cycles. Histograms show relative Nrf1a and Nrf1b expression normalized against 18S. (<b>C</b>)<b>.</b> Western blot of different mouse tissues probed with Nrf1 antibody. HEK293 cells transfected with pEF1-Nrf1a (lane 1), and pEF1-Nrf1b (lane 2) were used as controls for detection of the Nrf1a and Nrf1b isoforms by the Nrf1 antibody. Beta-actin was used as a loading control.