Controlling the elongation phase of transcription with P-TEFb.

Department of Medicine, Microbiology and Immunology, Rosalind Russell Medical Research Center, University of California, San Francisco, San Francisco, California 94143, USA.
Molecular Cell (Impact Factor: 14.46). 09/2006; 23(3):297-305. DOI: 10.1016/j.molcel.2006.06.014
Source: PubMed

ABSTRACT 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. In complex organisms, elongation control is critical for the regulated expression of most genes. In those organisms, the function of P-TEFb is influenced negatively by HEXIM proteins and 7SK snRNA and positively by a variety of recruiting factors. Phylogenetic analyses of the components of the human elongation control machinery indicate that the number of mechanisms utilized to regulate P-TEFb function increased as organisms developed more complex developmental patterns.

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