title: Transcription reinitiation by RNA polymerase III.
abstract: The retention of transcription proteins at an actively transcribed gene contributes to maintenance of the active transcriptional state and increases the rate of subsequent transcription cycles relative to the initial cycle. This process, called transcription reinitiation, generates the abundant RNAs in living cells. The persistence of stable preinitiation intermediates on activated genes representing at least a subset of basal transcription components has long been recognized as a shared feature of RNA polymerase (Pol) I, II and III-dependent transcription in eukaryotes. Studies of the Pol III transcription machinery and its target genes in eukaryotic genomes over the last fifteen years, has uncovered multiple details on transcription reinitiation. In addition to the basal transcription factors that recruit the polymerase, Pol III itself can be retained on the same gene through multiple transcription cycles by a facilitated recycling pathway. The molecular bases for facilitated recycling are progressively being revealed with advances in structural and functional studies. At the same time, progress in our understanding of Pol III transcriptional regulation in response to different environmental cues points to the specific mechanism of Pol III reinitiation as a key target of signaling pathway regulation of cell growth. This article is part of a Special Issue entitled: Transcription by Odd Pols.
authors.affiliation: Dipartimento di Bioscienze, Università degli Studi di Parma, Parco Area delle Scienze 23/A, 43124 Parma, Italy. giorgio.dieci@unipr.it
authors.forename: Giorgio
authors.initials: G
authors.lastname: Dieci
authors.forename: Maria Cristina
authors.initials: MC
authors.lastname: Bosio
authors.forename: Beatrice
authors.initials: B
authors.lastname: Fermi
authors.forename: Roberto
authors.initials: R
authors.lastname: Ferrari
mesh_terms: D000818:Animals; D006801:Humans; D012320:RNA Polymerase III / Q000378:metabolism*; D019474:Transcription Factors, TFIII / Q000378:metabolism; D061785:Transcription Initiation, Genetic; D061806:Transcription Termination, Genetic
chemical_list: D019474:Transcription Factors, TFIII; D012320:RNA Polymerase III