title: The yeast alpha 2 protein can repress transcription by RNA polymerases I and II but not III.
abstract: The alpha 2 protein of the yeast Saccharomyces cerevisiae normally represses a set of cell-type-specific genes (the a-specific genes) that are transcribed by RNA polymerase II. In this study, we determined whether alpha 2 can affect transcription by other RNA polymerases. We find that alpha 2 can repress transcription by RNA polymerase I but not by RNA polymerase III. Additional experiments indicate that alpha 2 represses RNA polymerase I transcription through the same pathway that it uses to repress RNA polymerase II transcription. These results implicate conserved components of the transcription machinery as mediators of alpha 2 repression and exclude several alternate models.
authors.affiliation: Department of Biochemistry and Biophysics, University of California, San Francisco 94143-0502.
authors.forename: B M
authors.initials: BM
authors.lastname: Herschbach
authors.forename: A D
authors.initials: AD
authors.lastname: Johnson
mesh_terms: D001483:Base Sequence; D003001:Cloning, Molecular; D004271:DNA, Fungal; D005656:Fungal Proteins / Q000378:metabolism*; D008969:Molecular Sequence Data; D011401:Promoter Regions, Genetic; D012318:RNA Polymerase I / Q000378:metabolism*; D012319:RNA Polymerase II / Q000378:metabolism*; D012320:RNA Polymerase III / Q000378:metabolism*; D012097:Repressor Proteins / Q000378:metabolism*; D012441:Saccharomyces cerevisiae / Q000201:enzymology / Q000235:genetics; D014158:Transcription, Genetic
chemical_list: D004271:DNA, Fungal; D005656:Fungal Proteins; D012097:Repressor Proteins; D012319:RNA Polymerase II; D012318:RNA Polymerase I; D012320:RNA Polymerase III