CUL-4A expression declines during granulocytic and macrophage differentiation.

(A) PLB-985 cells were induced to differentiate into granulocytes with 0.5% DMF. Northern blot analysis was used to measure CUL-4A mRNA at each time point. As controls, gp91^phox and β-actin mRNAs were analyzed.CUL-4A protein levels were measured by immunoblot analysis of 20 μg total lysate and actin was measured as a loading control. The amounts of mRNA or protein were quantified, normalized with respect to actin, and graphed (CUL-4A mRNA, ▪; CUL-4Aprotein, ●; gp91^phox mRNA, ▵). Representative results from 4 independent experiments are shown; SEM is reported in “Results.” (B) PLB-985 cells were induced to differentiate into macrophages with 100 nm PMA. Northern blot analysis was used to measure CUL-4A mRNA at each time point.CUL-4A protein level was measured as described for panel A. The same controls were measured, and the relative amounts of mRNA or protein were quantified and graphed as described for panel A.