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TRRAP and GCN5 are used by c-Myc to activate RNA polymerase III transcription.

ABSTRACT: Activation of RNA polymerase (pol) II transcription by c-Myc generally involves recruitment of histone acetyltransferases and acetylation of histones H3 and H4. Here, we describe the mechanism used by c-Myc to activate pol III transcription of tRNA and 5S rRNA genes. Within 2 h of its induction, c-Myc appears at these genes along with the histone acetyltransferase GCN5 and the cofactor TRRAP. At the same time, occupancy of the pol III-specific factor TFIIIB increases and histone H3 becomes hyperacetylated, but increased histone H4 acetylation is not detected at these genes. The rapid acetylation of histone H3 and promoter assembly of TFIIIB, c-Myc, GCN5, and TRRAP are followed by recruitment of pol III and transcriptional induction. The selective acetylation of histone H3 distinguishes pol III activation by c-Myc from mechanisms observed in other systems.

SUBMITTER: Kenneth NS

PROVIDER: S-EPMC1986588 | biostudies-literature | 2007 Sep

REPOSITORIES: biostudies-literature

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TRRAP and GCN5 are used by c-Myc to activate RNA polymerase III transcription.

Kenneth Niall S NS Ramsbottom Ben A BA Gomez-Roman Natividad N Marshall Lynne L Cole Philip A PA White Robert J RJ

Proceedings of the National Academy of Sciences of the United States of America 20070911 38

Activation of RNA polymerase (pol) II transcription by c-Myc generally involves recruitment of histone acetyltransferases and acetylation of histones H3 and H4. Here, we describe the mechanism used by c-Myc to activate pol III transcription of tRNA and 5S rRNA genes. Within 2 h of its induction, c-Myc appears at these genes along with the histone acetyltransferase GCN5 and the cofactor TRRAP. At the same time, occupancy of the pol III-specific factor TFIIIB increases and histone H3 becomes hyper ...[more]

PMID: 17848523

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