TRANSGENIC MICE FOR STUDY OF THE CDK8/19 CYCLIN-DEPENDENT KINASE KINASE-INDEPENDENT MECHANISMS OF ACTION

The CDK8 cyclin-dependent transcription-associated kinase and its less studied paralog, CDK19, regulate the expression of the dependant genes via several mechanisms. CDK8/19 can directly phosphorylate some transcription factors (ICN, STAT1), but at the same time these kinases being a component of the mediator complex regulate transcrition via interaction with chromatin in the promoter and enhancer regions of appropriate genes. Recently the papers have appeared showing that CDK8/19 has kinase-independent mechanisms of action through comparison of the effects of the kinase activity genetic inactivation and chemical inhibition. The study was aimed to generate transgenic mice capable of the induced and tissue-specific expression of the kinase-negative (showing no phosphorylation activity) form of CDK8, CDK8 (D173A), which could be later used to study the CDK8 kinase-independent mechanisms of action in vivo. We obtained four F0 transgenic animals by microinjection of linear DNA into the pronucleus, two of these animals became the ancestors of two distinct lines. The copy number of the integrated construct was measured for all F0 and the lines generated. This model may be used to study the kinase-independent properties of the CDK8/19 proteins.