Tat, Tat-associated kinase, and transcription.

The HIV-1 Tat protein is an RNA-binding transcriptional transactivator. Recent findings suggest that Tat associates with a cellular kinase that phosphorylates the carboxyl-terminal domain of the largest subunit of RNA polymerase II. Here we review, in brief, the role of Tat-associated kinase in Tat-activated transcription. We discuss evidence that suggests involvement of TFIIH and/or P-TEFb.