CDK12 and Polyuria: To establish the role of tubular CDK12 in the kidney, we first generated TEC-specific CDK12-knockout mice (CDK12flox/flox, Cdh16-Cre, CDK12RTEC-/-) using the Cre-LoxP system and found that CDK12RTEC-/- mice exhibited severe polyuria and polydipsia with mild renal dysfunction.18 To better mimic the downregulation of CDK12 expression via using a CDK12 inhibitor, we further generated conditional knockdown mice in which the CDK12 gene was downregulated in TEC by using the Cre-LoxP system.