Fig. 1.

Generation of Panx3^−/− mice. a Panx3 targeting vector from KOMP project ID CSD24494. The “Knockout-First” reporter tagged insertion promoter-driven cassette targets the second exon of Panx3, creating a truncated protein product. Source: www.knockoutmouse.org. b PCR genotyping showing lack of Panx3 exon2 amplicon in Panx3 null mice (Panx3^−/−). Upper primer is in the intron upstream of exon 2 in the floxed allele; the lower primer is in exon 2. PCR produces a 232-bp in the wild type (Panx3^+/+), but not in the null. c RT-PCR of mRNA from the mouse cartilage, using primers designed to amplify a 128-bp product bridging the intron between exons 3 and 4 of Panx3, revealed no amplification in the null mouse. d Western blots of protein lysates from wild type and Panx3^−/− mouse cartilage confirmed the complete absence of Panx3 protein in the Panx3^−/− mice. β-tubulin was used as loading control. e Litter size was significantly reduced in Panx3^+/− × Panx3^+/− crosses as well as Panx3^−/− × Panx3^−/− crosses compared to Panx3^+/+ × Panx3^+/+ crosses (N=13 litters, P<0.05; one-way ANOVA followed by Tukey test). weight of a 3-month-old Panx3^−/− male mice was not significantly different (ns) to Panx3^+/+ controls (N=10, t test, P>0.05). A 4-week-old (h) and an 8-month-old males examined (i) showed no overt morphological phenotypes when compared to Panx3^+/+ controls.