NPHS2 and Friedreich ataxia: PT2; Slc7a12), fibroblast (Col1a1), and myofibroblast (Acta2) of FA mice but not in podocytes (Nphs2), distal convoluted tubules (Slc12a3), intercalated cells of the collecting duct (Atp6v1g3), or principal cells (Aqp2).