(A) During normal development, prkcι/ζ play an essential function in polarity establishment when mesenchymal renal progenitors undergo a MET and concerted tubulogenesis to become epithelial cells and form the pronephros. When pronephros tubule epithelial identity is established, the activity of prkcι/ζ represses pax2a expression (either directly or indirectly) to maintain normal gene expression. (B) In the absence of prkcι/ζ, polarity is not properly established during MET. Further, pronephros cells in prkcι/ζ deficient embryos ectopically express pax2a, which leads (directly or indirectly) to misexpression of genes that include wt1a, wt1b, and podxl.