HIV Transcription Is Independent of Mediator Kinases.

While the roles in HIV transcription of many cyclin-dependent kinases (CDKs) have been well defined, little is known about the impact of mediator kinases (MDKs), CDK8 and CDK19, in this process. Mediator complexes containing CDK8 or CDK19 repress or activate the expression of selected genes. The aim of this study was to investigate the role of MDKs in HIV transcription. siRNA knockdown of both MDKs had no effect on HIV transcription. This result was confirmed using two MDK inhibitors, Cortistatin A (CA) and Senexin A (SnxA). Furthermore, neither CA nor SnxA inhibited viral reactivation in Jurkat cell models of HIV latency. Taken together, these results indicate that MDKs are not required for HIV transcription.