scholarly journals Rct1, a Nuclear RNA Recognition Motif-Containing Cyclophilin, Regulates Phosphorylation of the RNA Polymerase II C-Terminal Domain

2007 ◽  
Vol 27 (10) ◽  
pp. 3601-3611 ◽  
Author(s):  
Monika Gullerova ◽  
Andrea Barta ◽  
Zdravko J. Lorkovic
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Essential Gene ◽  
Close Association ◽  
Rna Recognition Motif ◽  
Rna Recognition ◽  
Terminal Domain ◽  
Important Player ◽  
Rnap Ii

ABSTRACT Phosphorylation of the C-terminal domain (CTD) of RNA polymerase II (RNAP II) is a dynamic process that regulates transcription and coordinates it with pre-mRNA processing. We show here that Rct1, a nuclear multidomain cyclophilin from Schizosaccharomyces pombe, is encoded by an essential gene that interacts with the CTD and regulates its phosphorylation in vivo. Downregulation of Rct1 levels results in increased phosphorylation of the CTD at both Ser2 and Ser5 and in a commensurate decrease in RNAP II transcription. In contrast, overexpression of Rct1 decreases phosphorylation on both sites. The close association of Rct1 with transcriptionally active chromatin suggests a role in regulation of RNAP II transcriptional activity. These data, together with the pleiotropic phenotype upon Rct1 deregulation, suggest that this multidomain cyclophilin is an important player in maintaining the correct phosphorylation code of the CTD and thereby regulating CTD function.

scholarly journals Role for the Ssu72 C-Terminal Domain Phosphatase in RNA Polymerase II Transcription Elongation

2006 ◽  
Vol 27 (3) ◽  
pp. 926-936 ◽  
Author(s):  
Mariela Reyes-Reyes ◽  
Michael Hampsey
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Elongation ◽  
Elongation Factor ◽  
Elongation Complex ◽  
Terminal Domain ◽  
Rnap Ii ◽  
Transcription Cycle

ABSTRACT The RNA polymerase II (RNAP II) transcription cycle is accompanied by changes in the phosphorylation status of the C-terminal domain (CTD), a reiterated heptapeptide sequence (Y1S2P3T4S5P6S7) present at the C terminus of the largest RNAP II subunit. One of the enzymes involved in this process is Ssu72, a CTD phosphatase with specificity for serine-5-P. Here we report that the ssu72-2-encoded Ssu72-R129A protein is catalytically impaired in vitro and that the ssu72-2 mutant accumulates the serine-5-P form of RNAP II in vivo. An in vitro transcription system derived from the ssu72-2 mutant exhibits impaired elongation efficiency. Mutations in RPB1 and RPB2, the genes encoding the two largest subunits of RNAP II, were identified as suppressors of ssu72-2. The rpb1-1001 suppressor encodes an R1281A replacement, whereas rpb2-1001 encodes an R983G replacement. This information led us to identify the previously defined rpb2-4 and rpb2-10 alleles, which encode catalytically slow forms of RNAP II, as additional suppressors of ssu72-2. Furthermore, deletion of SPT4, which encodes a subunit of the Spt4-Spt5 early elongation complex, also suppresses ssu72-2, whereas the spt5-242 allele is suppressed by rpb2-1001. These results define Ssu72 as a transcription elongation factor. We propose a model in which Ssu72 catalyzes serine-5-P dephosphorylation subsequent to addition of the 7-methylguanosine cap on pre-mRNA in a manner that facilitates the RNAP II transition into the elongation stage of the transcription cycle.

scholarly journals Functional Interaction between Ssu72 and the Rpb2 Subunit of RNA Polymerase II in Saccharomyces cerevisiae

2000 ◽  
Vol 20 (22) ◽  
pp. 8343-8351 ◽  
Author(s):  
Donald L. Pappas ◽  
Michael Hampsey
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Initiation ◽  
Essential Gene ◽  
Functional Interaction ◽  
Gene Encoding ◽  
General Transcription Factor ◽  
Physical Interactions ◽  
Rnap Ii

ABSTRACT SSU72 is an essential gene encoding a phylogenetically conserved protein of unknown function that interacts with the general transcription factor TFIIB. A recessive ssu72-1 allele was identified as a synthetic enhancer of a TFIIB (sua7-1) defect, resulting in a heat-sensitive (Ts−) phenotype and a dramatic downstream shift in transcription start site selection. Here we describe a new allele, ssu72-2, that confers a Ts− phenotype in a SUA7 wild-type background. In an effort to further define Ssu72, we isolated suppressors of thessu72-2 mutation. One suppressor is allelic toRPB2, the gene encoding the second-largest subunit of RNA polymerase II (RNAP II). Sequence analysis of the rpb2-100suppressor defined a cysteine replacement of the phylogenetically invariant arginine residue at position 512 (R512C), located within homology block D of Rpb2. The ssu72-2 andrpb2-100 mutations adversely affected noninduced gene expression, with no apparent effects on activated transcription in vivo. Although isolated as a suppressor of the ssu72-2Ts− defect, rpb2-100 enhanced the transcriptional defects associated with ssu72-2. The Ssu72 protein interacts directly with purified RNAP II in a coimmunoprecipitation assay, suggesting that the genetic interactions between ssu72-2 and rpb2-100 are a consequence of physical interactions. These results define Ssu72 as a highly conserved factor that physically and functionally interacts with the RNAP II core machinery during transcription initiation.

scholarly journals Wdr82 Is a C-Terminal Domain-Binding Protein That Recruits the Setd1A Histone H3-Lys4 Methyltransferase Complex to Transcription Start Sites of Transcribed Human Genes

2007 ◽  
Vol 28 (2) ◽  
pp. 609-618 ◽  
Author(s):  
Jeong-Heon Lee ◽  
David G. Skalnik
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Start Site ◽  
Histone H3 ◽  
Rna Recognition Motif ◽  
Start Site ◽  
Transcription Start ◽  
Transcription Start Sites ◽  
Terminal Domain ◽  
Rnap Ii

ABSTRACT Histone H3-Lys4 trimethylation is associated with the transcription start site of transcribed genes, but the molecular mechanisms that control this distribution in mammals are unclear. The human Setd1A histone H3-Lys4 methyltransferase complex was found to physically associate with the RNA polymerase II large subunit. The Wdr82 component of the Setd1A complex interacts with the RNA recognition motif of Setd1A and additionally binds to the Ser5-phosphorylated C-terminal domain of RNA polymerase II, which is involved in initiation of transcription, but does not bind to an unphosphorylated or Ser2-phosphorylated C-terminal domain. Chromatin immunoprecipitation analysis revealed that Setd1A is localized near the transcription start site of expressed genes. Small interfering RNA-mediated depletion of Wdr82 leads to decreased Setd1A expression and occupancy at transcription start sites and reduced histone H3-Lys4 trimethylation at these sites. However, neither RNA polymerase II (RNAP II) occupancy nor target gene expression levels are altered following Wdr82 depletion. Hence, Wdr82 is required for the targeting of Setd1A-mediated histone H3-Lys4 trimethylation near transcription start sites via tethering to RNA polymerase II, an event that is a consequence of transcription initiation. These results suggest a model for how the mammalian RNAP II machinery is linked with histone H3-Lys4 histone methyltransferase complexes at transcriptionally active genes.

scholarly journals Functional dissection of the catalytic mechanism of mammalian RNA polymerase II

2005 ◽  
Vol 83 (4) ◽  
pp. 497-504 ◽  
Author(s):  
Benoit Coulombe ◽  
Marie-France Langelier
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Catalytic Mechanism ◽  
Mutational Analysis ◽  
Structural Elements ◽  
Catalytic Mechanisms ◽  
Rnap Ii ◽  
Affinity Peptide

High resolution X-ray crystal structures of multisubunit RNA polymerases (RNAP) have contributed to our understanding of transcriptional mechanisms. They also provided a powerful guide for the design of experiments aimed at further characterizing the molecular stages of the transcription reaction. Our laboratory used tandem-affinity peptide purification in native conditions to isolate human RNAP II variants that had site-specific mutations in structural elements located strategically within the enzyme's catalytic center. Both in vitro and in vivo analyses of these mutants revealed novel features of the catalytic mechanisms involving this enzyme.Key words: RNA polymerase II, transcriptional mechanisms, mutational analysis, mRNA synthesis.

scholarly journals What’s all the phos about? Insights into the phosphorylation state of the RNA polymerase II C-terminal domain via mass spectrometry

2021 ◽  
Author(s):  
Blase Matthew LeBlanc ◽  
Rosamaria Yvette Moreno ◽  
Edwin Escobar ◽  
Mukesh Kumar Venkat Ramani ◽  
Jennifer S Brodbelt ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Phosphorylation State ◽  
Terminal Domain ◽  
Carboxy Terminal Domain ◽  
Protein Encoding ◽  
Small Nuclear Rnas ◽  
Rnap Ii ◽  
Carboxy Terminal ◽  
Encoding Genes

RNA polymerase II (RNAP II) is one of the primary enzymes responsible for expressing protein-encoding genes and some small nuclear RNAs. The enigmatic carboxy-terminal domain (CTD) of RNAP II and...

scholarly journals Human Cyclin K, a Novel RNA Polymerase II-Associated Cyclin Possessing Both Carboxy-Terminal Domain Kinase and Cdk-Activating Kinase Activity

1998 ◽  
Vol 18 (7) ◽  
pp. 4291-4300 ◽  
Author(s):  
Michael C. Edwards ◽  
Calvin Wong ◽  
Stephen J. Elledge
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Cell Cycle Progression ◽  
Large Subunit ◽  
Terminal Domain ◽  
Gene Coding ◽  
Acid Protein ◽  
Rnap Ii ◽  
Carboxy Terminal

ABSTRACT The gene coding for human cyclin K was isolated as aCPR (cell-cycle progression restoration) gene by virtue of its ability to impart a Far− phenotype to the budding yeast Saccharomyces cerevisiae and to rescue the lethality of a deletion of the G1 cyclin genes CLN1,CLN2, and CLN3. The cyclin K gene encodes a 357-amino-acid protein most closely related to human cyclins C and H, which have been proposed to play a role in regulating basal transcription through their association with and activation of cyclin-dependent kinases (Cdks) that phosphorylate the carboxyl-terminal domain (CTD) of the large subunit of RNA polymerase II (RNAP II). Murine and Drosophila melanogaster homologs of cyclin K have also been identified. Cyclin K mRNA is ubiquitously expressed in adult mouse and human tissues, but is most abundant in the developing germ cells of the adult testis and ovaries. Cyclin K is associated with potent CTD kinase and Cdk kinase (CAK) activity in vitro and coimmunoprecipitates with the large subunit of RNAP II. Thus, cyclin K represents a new member of the “transcription” cyclin family which may play a dual role in regulating Cdk and RNAP II activity.

scholarly journals FCP1, a Phosphatase Specific for the Heptapeptide Repeat of the Largest Subunit of RNA Polymerase II, Stimulates Transcription Elongation

2002 ◽  
Vol 22 (21) ◽  
pp. 7543-7552 ◽  
Author(s):  
Subhrangsu S. Mandal ◽  
Helen Cho ◽  
Sungjoon Kim ◽  
Kettly Cabane ◽  
Danny Reinberg
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Elongation ◽  
Carboxy Terminal Domain ◽  
Transcription Factor Iif ◽  
Transcript Elongation ◽  
Rnap Ii ◽  
Carboxy Terminal

ABSTRACT FCP1, a phosphatase specific for the carboxy-terminal domain of RNA polymerase II (RNAP II), was found to stimulate transcript elongation by RNAP II in vitro and in vivo. This activity is independent of and distinct from the elongation-stimulatory activity associated with transcription factor IIF (TFIIF), and the elongation effects of TFIIF and FCP1 were found to be additive. Genetic experiments resulted in the isolation of several distinct fcp1 alleles. One of these alleles was found to suppress the slow-growth phenotype associated with either the reduction of intracellular nucleotide concentrations or the inhibition of other transcription elongation factors. Importantly, this allele of fcp1 was found to be lethal when combined individually with two mutations in the second-largest subunit of RNAP II, which had been shown previously to affect transcription elongation.

scholarly journals RNA Polymerase II Carboxy-Terminal Domain Phosphorylation Is Required for Cotranscriptional Pre-mRNA Splicing and 3′-End Formation

2004 ◽  
Vol 24 (20) ◽  
pp. 8963-8969 ◽  
Author(s):  
Gregory Bird ◽  
Diego A. R. Zorio ◽  
David L. Bentley
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Kinase Inhibitors ◽  
Mrna Splicing ◽  
Pol Ii ◽  
Terminal Domain ◽  
Carboxy Terminal Domain ◽  
Carboxy Terminal ◽  
Ctd Phosphorylation

ABSTRACT We investigated the role of RNA polymerase II (pol II) carboxy-terminal domain (CTD) phosphorylation in pre-mRNA processing coupled and uncoupled from transcription in Xenopus oocytes. Inhibition of CTD phosphorylation by the kinase inhibitors 5,6-dichloro-1β-d-ribofuranosyl-benzimidazole and H8 blocked transcription-coupled splicing and poly(A) site cleavage. These experiments suggest that pol II CTD phosphorylation is required for efficient pre-mRNA splicing and 3′-end formation in vivo. In contrast, processing of injected pre-mRNA was unaffected by either kinase inhibitors or α-amanitin-induced depletion of pol II. pol II therefore does not appear to participate directly in posttranscriptional processing, at least in frog oocytes. Together these experiments show that the influence of the phosphorylated CTD on pre-mRNA splicing and 3′-end processing is mediated by transcriptional coupling.

scholarly journals RNA Polymerase II Localizes in Tetrahymena thermophila Meiotic Micronuclei When Micronuclear Transcription Associated with Genome Rearrangement Occurs

2004 ◽  
Vol 3 (5) ◽  
pp. 1233-1240 ◽  
Author(s):  
Kazufumi Mochizuki ◽  
Martin A. Gorovsky
Keyword(s):  
Life Cycle ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Genome Rearrangement ◽  
Tetrahymena Thermophila ◽  
Germ Line ◽  
Essential Gene ◽  
Gene Encoding ◽  
Sexual Process ◽  
Rnap Ii

ABSTRACT The germ line micronucleus in Tetrahymena thermophila is transcriptionally silent in vegetatively growing cells. However, micronuclear transcription has been observed in the early (“crescent”) stages of the sexual process, conjugation. This transcription is proposed to play a central role in identifying sites for subsequent genome rearrangements that accompany development of the somatic macronucleus from the micronucleus. RPB3 (cnjC), a gene encoding a protein homologous to the third largest subunit of RNA polymerase II (RNAP II), was previously reported to be expressed specifically during conjugation, suggesting a role in micronucleus-specific transcription. Rpb3p localized in the micronucleus only during the meiotic prophase, when micronuclear transcription occurs, and its intranuclear distribution is strikingly similar to that for previously described sites of micronuclear RNA synthesis. By contrast, Rpc5p, the homologous subunit shared by RNAPs I and III, was not detectable in the micronucleus at any stage of the life cycle. However, Rpb3p is not specific to the transcribing micronucleus. Like Rpc5p, it also localizes to macronuclei in all stages of the life cycle. Rpb3p is encoded by a unique, essential gene in Tetrahymena. Thus, RNAP II is associated with both somatic transcription and crescent transcription and probably has an important role in genome rearrangement.

Sign in / Sign up

Export Citation Format

Share Document