• PMID: 28384194
• Gene Name: SLC9A3
• Condition: Obstructive azoospermia, CBAVD, Male infertility
• Association: Associated
• Sex: Male
• Infertility type: Male infertility
• Other associated phenotypes: Obstructive azoospermia, CBAVD, Male infertility

Loss of SLC9A3 decreases CFTR protein and causes obstructed azoospermia in mice

Wang YY, Lin YH, Wu YN, Chen YL, Lin YC, Cheng CY, Chiang HS.

Mutations in the cystic fibrosis transmembrane conductance regulator (CFTR) gene cause cystic fibrosis (CF) and are associated with congenital bilateral absence of the vas deferens (CBAVD), which is the major cause of infertility in male patients with CF. However, most Taiwanese patients with CBAVD do not carry major CFTR mutations. Some patients have a single copy deletion of the solute carrier family 9 isoform 3 (SLC9A3) gene. SLC9A3 is a Na+/H+ exchanger, and depleted Slc9a3 in male mice causes infertility due to the abnormal dilated lumen of the rete testis and efferent ductules. Furthermore, SLC9A3 interacts with CFTR in the pancreatic duct and functions as a genetic modifier of CF. However, SLC9A3 function and its relation to CFTR expression in the male reproductive tract in vivo remain elusive. In the present study, we found that CFTR expression was dramatically decreased in the epididymis and vas deferens of Slc9a3 knockout mice. Adult Slc9a3-/- mice showed not only significantly decreased epididymis and vas deferens weight but also increased testis weight. Furthermore, Slc9a3-/- mice developed obstructive azoospermia because of abnormal abundant secretions and calcification in the lumen of the reproductive tract. Ultrastructural analysis of the epithelium in Slc9a3-/-epididymis and vas deferens displayed disorganized and reduced number of stereocilia and numerous secretory apparatuses. Our data revealed that interdependence between SLC9A3 and CFTR is critical for maintaining a precise microenvironment in the epithelial cytoarchitecture of the male reproductive tract. The Slc9a3-deficient mice with impaired male excurrent ducts in this study provide proof for our clinical findings that some Taiwanese of CBAVD carry SLC9A3 deletion but without major CFTR mutations. FAU - Wang, Ya-Yun AU - Wang YY AD - Department of Chemistry, Fu Jen Catholic University, New Taipei City, Taiwan. AD - Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, Taiwan. FAU - Lin, Ying-Hung AU - Lin YH AD - Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, Taiwan. FAU - Wu, Yi-No AU - Wu YN AD - Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, Taiwan. FAU - Chen, Yen-Lin AU - Chen YL AD - Department of Chemistry, Fu Jen Catholic University, New Taipei City, Taiwan. AD - Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, Taiwan. AD - Department of Pathology, Cardinal Tien Hospital, New Taipei City, Taiwan. FAU - Lin, Yung-Chih AU - Lin YC AD - Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, Taiwan. FAU - Cheng, Chiao-Yin AU - Cheng CY AD - Graduate Institute of Biomedical and Pharmaceutical Science, Fu Jen Catholic University, New Taipei City, Taiwan.