GJA1 and male infertility: Further analysis revealed that PA1 was necessary for the transcription of a subset of genes that are vital for proper Sertoli cell functioning, including those genes associated with cell-adhesion and cytoskeleton organization, such as Cx43. In addition, we find that PA1 cooperates with JUN to regulate Cx43, whose disruption also results in male infertility, resembling that of Amh-pa1−/− mice.