Other proteins essential for terminal differentiation of kidney tubules were also expressed in the implants: cubulin present in the apical brush border of proximal tubules, where it functions with megalin in uptake of small proteins; uromodulin, an apical protein in ascending loops of Henle and mutated in medullary cystic kidney disease (Ovunc et al., 2011, Turner et al., 2003); and TRPV5, involved in calcium transport in the distal convoluted tubule. Here, TRPV5 is linked to autosomal dominant medullary cystic kidney disease with or without hyperuricemia.