High cellular turnover precedes the development of cysts.

<p>Representative pictures of renal cortex from 30 (A, B, E, F) and 50 day old mice (C, D, G, H). Ctr (A, C, E, G) and Dicer cKO (B, D, F, H) renal sections were stained with anti-ki67 (marker of proliferation) (A-D) and anti-Cleaved Caspase 3 (marker of apoptosis) (E-H). Before developing the Dicer-induced glomerulocystic phenotype, the epithelium lining the dilating structure is already immunoreactive to the proliferation marker ki67 (B). Higher proliferation rate is evident also in dilated structure (D). Glomerular and tubular cells of Dicer cKO mice at both P30 and P50 (F, H) were positive for the apoptosis marker, Cleaved Caspase 3. (A-H) Magnification 40X.