Mediator complexes and eukaryotic transcription regulation: an overview.
Mediator is an essential component of the RNA polymerase II-mediated transcription machinery. This component plays a key role both in the stimulation of basal transcription and in the regulation of eukaryotic mRNA synthesis. The Saccharomyces cerevisiae Mediator complex was the first to be studied and consists of at least 20 different subunits with multiple activities. Afterwards, its subunit composition was determined and related functions of C. elegans, Drosophila and mammalian complexes show a striking evolutionary conservation both of the structure and function from yeast to man. Recently, yeast studies strongly suggest additional roles for Mediator in coordinating transcription initiation with downstream transcriptional events in the coding region of genes; consequently, new models of recruitment-coupled regulation have been indicated. Further studies on transcription machinery should expand our knowledge of the pathways in which variant components of Mediator, or variant proteins interacting directly or in complexes, represent risk factors for complex inheritable disease.
Casamassimi
Amelia
A
Department of General Pathology, Division of Clinical Pathology, 1st School of Medicine, II University of Naples, Via L. De Crecchio 7, 80138-Naples, Italy.
Napoli
Claudio
C
D000818:Animals; D005057:Eukaryotic Cells / Q000378:metabolism*; D019143:Evolution, Molecular; D005786:Gene Expression Regulation; D006801:Humans; D008954:Models, Biological; D021122:Protein Subunits / Q000235:genetics / Q000378:metabolism; D012319:RNA Polymerase II / Q000378:metabolism; D029701:Saccharomyces cerevisiae Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
D021122:Protein Subunits; D029701:Saccharomyces cerevisiae Proteins; D014157:Transcription Factors; D012319:RNA Polymerase II