Generation of Tiparp−/− mice. (A) U373-CD14 cells were transiently transfected with the indicated siRNA for 48 h. The levels of ZC3HAV1, TIPARP, and PARP12 mRNA were measured by quantitative reverse transcription-PCR. (B) Schematic representation of Tiparp gene targeting. The targeting vector was constructed by replacing exon 2 of Tiparp with a neomycin resistance gene. E, exon; NEO, phosphoglycerate kinase promoter-driven neomycin-resistance gene cassette; B, BamH1. (C) Southern blot analysis of genomic DNA from Tiparp+/+, Tiparp+/−, and Tiparp−/− mice. Genomic DNA was separated by electrophoresis after digestion with BamH1 and hybridized with the radiolabeled probe shown in B. (D) Total RNAs from Tiparp+/+ and Tiparp−/− MEFs were subjected to RT-PCR analysis of the expression of Tiparp and Actb mRNA.