Pkd1 is required for male reproductive tract development

Reproductive tract abnormalities and male infertility have higher incidence in ADPKD patients than in general populations. In this work, we reveal that Pkd1, whose mutations account for 85% of ADPKD cases, is essential for male reproductive tract development. Disruption of Pkd1 caused multiple organ defects in the murine male reproductive tract. The earliest visible defect in the Pkd1^-/- reproductive tract was cystic dilation of the efferent ducts, which are derivatives of the mesonephric tubules. Epididymis development was delayed or arrested in the Pkd1^-/- mice. No sign of epithelial coiling was seen in the null mutants. Disruption of Pkd1 in epithelium alone using the Pax2-cre mice was sufficient to cause efferent duct dilation and coiling defect in the epididymis, suggesting that Pkd1 is critical for epithelium development and maintenance in male reproductive tract. In-depth analysis showed that Pkd1 is required to maintain tubulin cytoskeleton and important for Tgf-β/Bmp signal transduction in epithelium of male reproductive tract. Altogether, our results for the first time provide direct evidence for developmental roles of Pkd1 in the male reproductive tract and provide new insights in reproductive tract abnormalities and infertility in ADPKD patients.