Figure 1.
Effect of p110δ inactivation on PI3K expression and activity in primary splenic B cells. (A) Expression of class I PI3K isoforms in total cell lysates (50 μg/lane), as assessed by immunoblotting. Left and right panels are from 2 independent analyses, carried on pooled lysates from 3 mice each. (B) Class IA-associated lipid kinase activity present in primary splenic B cells. Cell extracts were purified using YpVPMLG peptide complexes as described in “Materials and methods,” and assayed by an in vitro PI3K assay using PtdIns(4,5)P2 as substrate. PI3K activity is presented relative to that found in WT cells. Error bars indicate SD.
