Establishment of MEF derived from wild-type and PKD2 mutation embryos MEF were acquired from PKD2 TG embryos or Pkd2 KO embryos during development (13.5 days) [11]. Heads and limes were removed from embryos. The remaining embryonic tissues were minced and dispersed in 0.05% trypsin prior to incubation at 37℃ for 15 min. Cells were plated in Dulbecco's Modified Eagle's Medium of Defined Minimal Essential medium (Welgene Biotech, Taipei, Taiwan) supplemented with 10% fetal bovine serum (Welgene Biotech) and were cultured at 37℃ in an atmosphere of 5% CO2 until confluent growth was achieved. MEF cells were frozen as stocks at the second passage and were used for the subsequent studies at the third passage.