The positive transcription elongation factor, P-TEFb, is a multiprotein complex that plays an essential role in the regulation of transcription by RNA polymerase II (Pol II) in eukaryotes. [1] Immediately following initiation Pol II becomes trapped in promoter proximal paused positions on the majority of human genes (Figure 1).

Feb 2, 2023 · The positive transcription elongation factor b (P-TEFb) is composed of cyclins T1 or T2 and cyclin-dependent kinase 9 that regulate the elongation phase of transcription by RNA polymerase II.

In this review article, I will summarize our knowledge about basic P-TEFb functions, the regulatory mechanism of P-TEFb-dependent transcription, P-TEFb’s involvement in biological processes and diseases, and current approaches to manipulating P-TEFb functions for …

May 8, 2018 · Three major positive transcription elongation factor b (P-TEFb)-containing complexes have been identified in mammals: 7SK small nuclear ribonucleoprotein–P-TEFb (7SK–P-TEFb), bromodomain ...

Escape from the action of N-TEF requires the action of at least one positive transcription elongation factor (P-TEF), eventually identified as P-TEFb (52). P-TEFb allows the transition into productive elongation, producing long transcripts from which mRNAs are derived.

Sep 2, 2009 · Among them, transcription elongation is positively regulated by the positive transcription elongation factor b (P-TEFb), consisting of CDK9 and cyclin T1, T2 or K. P-TEFb enables transition from abortive to productive transcription elongation by phosphorylating carboxyl-terminal domain (CTD) in RNAPII and negative transcription elongation factors.

Escape from the action of N-TEF requires the action of at least one positive transcription elongation factor (P-TEF), eventually identified as P-TEFb (52). P-TEFb allows the transition into productive elongation, producing long transcripts from which mRNAs are derived.

The positive transcription elongation factor b (P-TEFb) is a cyclin-dependent kinase that controls the elongation phase of transcription by RNA polymerase II (RNAPII). This process is made possible by the reversal of effects of negative elongation factors that include NELF and DSIF.

P-TEFb, a heterodimer of cyclinT1 and the kinase CDK9, plays a pivotal role in enhancing transcription from the 5′LTR (Wei et al., 1998). Because of its prominent role in controlling transcription, cellular P-TEFb levels are tightly regulated.

By antagonizing negative elongation factors and phosphorylating the C-terminal domain of RNA polymerase II, P-TEFb facilitates the elongation and co-transcriptional processing of nascent transcripts. This step is critical for the expression of most eukaryotic genes.