(A) Schematic diagram of conditional inactivation of Pkd1 in Arl13b-EGFPtg:cPkd1 mice.. (B) Representative images of H and E staining of kidneys from Arl13b-EGFPtg:cPkd1 mice (2 months after doxycycline removal); three independent experiments. Sagittal sections of kidneys (left, scale bar, 0.5 cm) and higher magnification (middle and right, scale bar = 100 μm) are shown at the indicated times. (C) Representative kidney sections from Arl13b-EGFPtg:cPkd1 mice (2 months after doxycycline removal) were immuno-labeled with antibodies against EGFP and acetylated tubulin; three independent experiments. Scale bar, 5 μm. (D) Cilia length increased with the progression of cyst formation from kidney sections of Arl13b-EGFPtg:cPkd1 mice (2 months after doxycycline removal). (E) Genomic PCR for pIMCD cells isolated from Arl13b-EGFPtg:cPkd1 mice (2 weeks after doxycycline removal); three independent experiments. The PCR product for the floxed allele,~400 bp; for wt,~200 bp; for the Deletion alleles (exons 2–4 of Pkd1 deleted) of Del,~650 bp; for non-Del,~1650 bp. The weak band at ~1650 bp in the far right lane is the residual amount of intact Pkd1, which may be due to the contamination of non-tubule cells or tubule cells from S3 straight segment. The bands larger than 200 bp, both before and after doxycycline treatment, are non-specific bands (absent at shorter PCR extension times).