Sall1 expression in terminally differentiated nephron segments. Sections from P0 wild-type kidney stained for terminally differentiated nephron markers: LTL, proximal tubule; THP, thick ascending limb; PNA, distal tubule; AQP1, thick and thin descending limb; NKCC2, thick ascending limb; cytokeratin, ureter and collecting duct; and Sall1. Scale bars: 100 μm.