The yeast alpha 2 protein can repress transcription by RNA polymerases I and II but not III.

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.

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Cell-type-specific regulation of RNA polymerase I transcription: a new frontier

BioEssays ◽

10.1002/bies.20430 ◽

2006 ◽

Vol 28 (7) ◽

pp. 719-725 ◽

Cited By ~ 8

Author(s):

Hung Tseng

Keyword(s):

Rna Polymerase ◽

Rna Polymerase I ◽

Cell Type ◽

New Frontier ◽

Cell Type Specific ◽

Specific Regulation ◽

Polymerase I

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Phosphorylation of RNA polymerases: specific association of protein kinase NIl with RNA polymerase I

Philosophical Transactions of the Royal Society of London Series B Biological Sciences ◽

10.1098/rstb.1983.0046 ◽

1983 ◽

Vol 302 (1108) ◽

pp. 135-142 ◽

Cited By ~ 11

Keyword(s):

Protein Kinase ◽

Rna Polymerase ◽

Rna Synthesis ◽

Rna Polymerase Iii ◽

Rna Polymerases ◽

Rna Polymerase I ◽

Liver Protein ◽

Protein Kinase N ◽

Polymerase I

The activities of the three DNA-dependent RNA polymerases from a rapidly growing rat tumour, Morris hepatoma 3924 A, and from rat liver were examined. The activity of RNA polymerase I was higher in the tumour than in the liver. The enhanced capacity for RNA synthesis was a result of a higher concentration of polymerase I in the tumour as well as of an activation of this enzyme vivo. The possibility that the high specific activity of the hepatoma polymerase I resulted from phosphorylation was investigated. Two major cyclic-AMP-independent nuclear casein kinases (NI and N il) were identified; the activity of protein kinase N il in the tumour was ten times that in liver. Protein kinase N il was capable of activating and phosphorylating RNA polymerase I in vitro . This kinase could also stimulate RNA polymerase II activity, although to a lesser extent than RNA polymerase I. RNA polymerase III was not affected by protein kinase NIL Protein kinase N il was tightly associated with polymerase I and was found even in purified preparations of the polymerase. Antibodies against both RNA polymerase I and protein kinase N il were present in sera of patients with certain rheumatic autoimmune diseases. These results imply that RNA polymerase I and protein kinase NIl are in close association in vivo as well as in vitro and that polymerase phosphorylation may regulate the rate of ribosomal RNA synthesis in the cell.

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A Drosophila anti-RNA polymerase II antibody recognizes a plant nucleolar antigen, RNA polymerase I, which is mostly localized in fibrillar centres

Journal of Cell Science ◽

10.1242/jcs.100.1.99 ◽

1991 ◽

Vol 100 (1) ◽

pp. 99-107 ◽

Cited By ~ 1

Author(s):

M. Martin ◽

F.J. Medina

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Large Subunit ◽

Rna Polymerases ◽

Rna Polymerase I ◽

Rrna Synthesis ◽

Dense Fibrillar Component ◽

Transition Area ◽

Fibrillar Component ◽

Polymerase I

The distribution of nucleolar RNA polymerase in the nucleolus of onion root meristematic cells has been studied by means of an antibody originally raised against Drosophila RNA polymerase II. This antibody recognizes the homologous domains of the large subunit of the enzyme, which are highly conserved throughout evolution in the three classes of eucaryotic RNA polymerases. Given that RNA polymerase I is confined to the nucleolus, and that the onion cell nucleolus lacks digitations of extranucleolar chromatin, we conclude that the nucleolar enzyme localized is RNA polymerase I. A quantitative approach, independent of the existence of borderlines between nucleolar fibrillar centres and the dense fibrillar component, allowed us to show that the enzyme is localized in fibrillar centres and in the transition area between them and the dense fibrillar component, in parallel with the nucleolar DNA. These results, together with previous autoradiographic, cytochemical and immunocytochemical results, in this and other species, lead us to conclude that the activation of rDNA for transcription occurs in the fibrillar centres and pre-rRNA synthesis is expressed at the transition area between fibrillar centres and the dense fibrillar component. Fibrillar centres are connected to each other by extended RNA polymerase-bound DNA fibres, presumably active in transcription. This work provides evidence of the high evolutionary conservation of some domains of the large subunit of RNA polymerases and of the existence of fibrillar centres in the nucleolus of plant cells, totally homologous to those described in mammalian cells.

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Control points in eucaryotic ribosome biogenesis

Biochemistry and Cell Biology ◽

10.1139/o91-002 ◽

1991 ◽

Vol 69 (1) ◽

pp. 5-22 ◽

Cited By ~ 56

Author(s):

D. E. Larson ◽

P. Zahradka ◽

B. H. Sells

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Ribosomal Proteins ◽

Ribosome Biogenesis ◽

Rna Polymerase Iii ◽

Ribosomal Subunits ◽

Rrna Species ◽

Polymerase I ◽

Ribosomal Precursor ◽

Precursor Molecules

Ribosome biogenesis in eucaryotic cells involves the coordinated synthesis of four rRNA species, transcribed by RNA polymerase I (18S, 28S, 5.8S) and RNA polymerase III (5S), and approximately 80 ribosomal proteins translated from mRNAs synthesized by RNA polymerase II. Assembly of the ribosomal subunits in the nucleolus, the site of 45S rRNA precursor gene transcription, requires the movement of 5S rRNA and ribosomal proteins from the nucleoplasm and cytoplasm, respectively, to this structure. To integrate these events and ensure the balanced production of individual ribosomal components, different strategies have been developed by eucaryotic organisms in response to a variety of physiological changes. This review presents an overview of the mechanisms modulating the production of ribosomal precursor molecules and the rate of ribosome biogenesis in various biological systems.Key words: rRNA, ribosomal proteins, nucleolus, ribosome.

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The REB1 site is an essential component of a terminator for RNA polymerase I in Saccharomyces cerevisiae

Molecular and Cellular Biology ◽

10.1128/mcb.13.1.649-658.1993 ◽

1993 ◽

Vol 13 (1) ◽

pp. 649-658

Author(s):

W H Lang ◽

R H Reeder

Keyword(s):

Saccharomyces Cerevisiae ◽

Rna Polymerase ◽

Protein Binding ◽

Binding Site ◽

Rna Polymerase I ◽

Recognition Sequence ◽

Sequence Context ◽

Yeast Saccharomyces Cerevisiae ◽

Essential Component ◽

Polymerase I

We have identified a terminator for transcription by RNA polymerase I in the genes coding for rRNA of the yeast Saccharomyces cerevisiae. The terminator is located 108 bp downstream of the 3' end of the mature 25S rRNA and shares several characteristics with previously studied polymerase I terminators in the vertebrates. For example, the yeast terminator is orientation dependent, is inhibited by its own sequence, and forms RNA 3' ends 17 +/- 2 bp upstream of an essential protein binding site. The recognition sequence for binding of the previously cloned REB1 protein (Q. Ju, B. E. Morrow, and J. R. Warner, Mol. Cell. Biol. 10:5226-5234, 1990) is an essential component of the terminator. In addition, the efficiency of termination depends upon sequence context extending at least 12 bp upstream of the REB1 site.

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Superimposed Promoter Sequences of the Adenoviral E2 Early RNA Polymerase III and RNA Polymerase II Transcription Units

Journal of Biological Chemistry ◽

10.1074/jbc.m007036200 ◽

2000 ◽

Vol 276 (1) ◽

pp. 827-834 ◽

Cited By ~ 2

Author(s):

Dina Ellsworth ◽

Renee L. Finnen ◽

S. J. Flint

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Rna Polymerase Iii ◽

Promoter Sequences ◽

Polymerase Iii ◽

Rna Polymerase Ii Transcription

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The telomeric Cdc13–Stn1–Ten1 complex regulates RNA polymerase II transcription

Nucleic Acids Research ◽

10.1093/nar/gkz279 ◽

2019 ◽

Vol 47 (12) ◽

pp. 6250-6268 ◽

Cited By ~ 2

Author(s):

Olga Calvo ◽

Nathalie Grandin ◽

Antonio Jordán-Pla ◽

Esperanza Miñambres ◽

Noelia González-Polo ◽

...

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Genome Stability ◽

Elongation Factor ◽

Yeast Saccharomyces Cerevisiae ◽

Replication Fork Progression ◽

Genome Wide ◽

Length Regulation ◽

Transcription Regulators ◽

Rna Polymerase Ii Transcription

Abstract Specialized telomeric proteins have an essential role in maintaining genome stability through chromosome end protection and telomere length regulation. In the yeast Saccharomyces cerevisiae, the evolutionary conserved CST complex, composed of the Cdc13, Stn1 and Ten1 proteins, largely contributes to these functions. Here, we report genetic interactions between TEN1 and several genes coding for transcription regulators. Molecular assays confirmed this novel function of Ten1 and further established that it regulates the occupancies of RNA polymerase II and the Spt5 elongation factor within transcribed genes. Since Ten1, but also Cdc13 and Stn1, were found to physically associate with Spt5, we propose that Spt5 represents the target of CST in transcription regulation. Moreover, CST physically associates with Hmo1, previously shown to mediate the architecture of S-phase transcribed genes. The fact that, genome-wide, the promoters of genes down-regulated in the ten1-31 mutant are prefentially bound by Hmo1, leads us to propose a potential role for CST in synchronizing transcription with replication fork progression following head-on collisions.

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