FIG. 1.

Targeted disruption of murine p110δ gene. (A) A targeting construct that would replace the indicated exons with a neomycin resistance cassette was developed. The locations of the 3′ external probe and PCR primers (P1, P2, and P3) for genotyping are indicated. Restriction enzyme sites: Sa, SacI; K, KpnI; St, StuI. DTA, diphtheria toxin A; Wt, wild type. (B) Southern blot analysis of KpnI-digested genomic DNA from p110δ heterozygous mice probed with the indicated probe. The positions of the mutant 5.8-kb and wild-type 4.3-kb KpnI fragments are indicated. (C) Absence of p110δ protein expression in p110δ^−/− mice. Total splenic lysate (2 mg) was used for immunoprecipitation and Western blot analysis with rabbit polyclonal anti-p110δ antibodies (see Materials and Methods).