Effect of PIP5KI overexpression on PtdIns(4,5)P₂ levels in renal epithelial cells.

<p>Non-polarized (A) or polarized (B) mCCD cells infected with either control adenovirus or virus encoding PIP5KIβ, PIP5KIα, or PIP5KIγ were radiolabeled with ³²P_i for 4 h then acidic lipids collected and analyzed by TLC. PtdIns(4,5)P₂ was quantified as the percent of total acidic phospholipids recovered in each sample. Each graph represents the mean +/− SE of at least four experiments performed in duplicate. One way ANOVA with Bonferroni correction was performed to determine statistical significance (**p<0.01 *p<0.05). Whereas expression of each isoform increased cellular PtdIns(4,5)P₂ levels in non-polarized cells, only PIP5KIβ had a significant effect on PtdIns(4,5)P₂ in polarized cells.