Prorenin receptor is essential for normal podocyte structure and function

The prorenin receptor is an accessory subunit of the vacuolar H ⁺-ATPase, suggesting that it has fundamental functions beyond activation of the local renin-angiotensin system. Podocytes express the prorenin receptor, but its function in these cells is unknown. Here, podocyte-specific, conditional, prorenin receptor-knockout mice died of kidney failure and severe proteinuria within 4 weeks of birth. The podocytes of these mice exhibited foot process effacement with reduced and altered localization of the slit-diaphragm proteins nephrin and podocin. Furthermore, the podocytes contained numerous autophagic vacuoles, confirmed by enhanced accumulation of microtubule- associated protein 1 light chain 3-positive intracellular vesicles. Ablation of the prorenin receptor selectively suppressed expression of the V₀ c-subunit of the vacuolar H⁺-ATPase in podocytes, resulting in deacidification of intracellular vesicles. In conclusion, the prorenin receptor is important for the maintenance of normal podocyte structure and function.