In this work, we have demonstrated that xCEP290-depleted embryos exhibited edema and dilated pronephric tubule with elongated cilia; the pronephric tubule, but not elongated cilia, was rescued by the treatment of tolvaptan, which is a vasopressin V2 receptor antagonist and prescribed for patients with ADPKD (68, 69, 71). Here, AVPR2 is linked to autosomal dominant polycystic kidney disease.