Next, to clarify the specific contribution of FKBP12.6 in FK506-induced male infertility, we prepared several tagged proteins including GST-tagged FKBP12, GST-tagged FKBP12.6, His-tagged PPP3CC, and His-tagged PPP3R2, for conducting the pull-down experiments. This evidence concerns the gene FKBP1A and male infertility.