Phosphorylation of AQP2 at serine 256 promotes AQP2 trafficking to the apical plasma membrane [30], and phosphorylation of AQP2 at serine 261 is linked to ubiquitination [31], which is consistent with the finding that aldosterone increases urine production and decreases apical AQP2 expression in rats with diabetes insipidus [22]. This evidence concerns the gene AQP2 and diabetes insipidus.