scholarly journals Control of formation of two distinct classes of RNA polymerase II elongation complexes

1992 ◽  
Vol 12 (5) ◽  
pp. 2078-2090
Author(s):  
N F Marshall ◽  
D H Price
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
In Vivo Experiments ◽  
Rapid Generation ◽  
Transcription Complexes ◽  
Productive Elongation

We have examined elongation by RNA polymerase II initiated at a promoter and have identified two classes of elongation complexes. Following initiation at a promoter, all polymerase molecules enter an abortive mode of elongation. Abortive elongation is characterized by the rapid generation of short transcripts due to pausing of the polymerase followed by termination of transcription. Termination of the early elongation complexes can be suppressed by the addition of 250 mM KCl or 1 mg of heparin per ml soon after initiation. Elongation complexes of the second class carry out productive elongation in which long transcripts can be synthesized. Productive elongation complexes are derived from early paused elongation complexes by the action of a factor which we call P-TEF (positive transcription elongation factor). P-TEF is inhibited by 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole at concentrations which have no effect on the initiation of transcription. By using templates immobilized on paramagnetic particles, we show that isolated preinitiation complexes lack P-TEF and give rise to transcription complexes which can carry out only abortive elongation. The ability to carry out productive elongation can be restored to isolated transcription complexes by the addition of P-TEF after initiation. A model is presented which describes the role of elongation factors in the formation and maintenance of elongation complexes. The model is consistent with the available in vivo data concerning control of elongation and is used to predict the outcome of other potential in vitro and in vivo experiments.

scholarly journals Control of formation of two distinct classes of RNA polymerase II elongation complexes.

1992 ◽  
Vol 12 (5) ◽  
pp. 2078-2090 ◽  
Author(s):  
N F Marshall ◽  
D H Price
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
In Vivo Experiments ◽  
Rapid Generation ◽  
Transcription Complexes ◽  
Productive Elongation

We have examined elongation by RNA polymerase II initiated at a promoter and have identified two classes of elongation complexes. Following initiation at a promoter, all polymerase molecules enter an abortive mode of elongation. Abortive elongation is characterized by the rapid generation of short transcripts due to pausing of the polymerase followed by termination of transcription. Termination of the early elongation complexes can be suppressed by the addition of 250 mM KCl or 1 mg of heparin per ml soon after initiation. Elongation complexes of the second class carry out productive elongation in which long transcripts can be synthesized. Productive elongation complexes are derived from early paused elongation complexes by the action of a factor which we call P-TEF (positive transcription elongation factor). P-TEF is inhibited by 5,6-dichloro-1-beta-D-ribofuranosylbenzimidazole at concentrations which have no effect on the initiation of transcription. By using templates immobilized on paramagnetic particles, we show that isolated preinitiation complexes lack P-TEF and give rise to transcription complexes which can carry out only abortive elongation. The ability to carry out productive elongation can be restored to isolated transcription complexes by the addition of P-TEF after initiation. A model is presented which describes the role of elongation factors in the formation and maintenance of elongation complexes. The model is consistent with the available in vivo data concerning control of elongation and is used to predict the outcome of other potential in vitro and in vivo experiments.

scholarly journals A Cdk9-PP1 kinase-phosphatase switch regulates the elongation-termination transition of RNA polymerase II

2017 ◽  
Author(s):  
Pabitra K. Parua ◽  
Gregory T. Booth ◽  
Miriam Sansó ◽  
Bradley Benjamin ◽  
Jason C. Tanny ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
Bistable Switch ◽  
Pol Ii ◽  
Mrna Maturation ◽  
Cleavage And Polyadenylation ◽  
Transcription Complexes

The end of the RNA polymerase II (Pol II) transcription cycle is strictly regulated to ensure proper mRNA maturation and prevent interference between neighboring genes1. Pol II slowing downstream of the cleavage and polyadenylation signal (CPS) leads to recruitment of cleavage and polyadenylation factors and termination2, but how this chain of events is initiated remains unclear. In a chemical-genetic screen, we identified protein phosphatase 1 (PP1) isoforms as substrates of human positive transcription elongation factor b (P-TEFb), the cyclin-dependent kinase 9 (Cdk9)-cyclin T1 complex3. Here we show that Cdk9 and PP1 govern phosphorylation of the conserved transcription factor Spt5 in the fission yeast Schizosaccharomyces pombe. Cdk9 phosphorylates both Spt5 and a negative regulatory site on the PP1 isoform Dis24. Sites phosphorylated by Cdk9 in the Spt5 carboxy-terminal domain (CTD) are dephosphorylated by Dis2 in vitro, and Cdk9 inhibition in vivo leads to rapid Spt5 dephosphorylation that is retarded by concurrent Dis2 inactivation. Chromatin immunoprecipitation and sequencing (ChIP-seq) analysis indicates that Spt5 is dephosphorylated as transcription complexes traverse the CPS, prior to or concomitant with slowing of Pol II5. A Dis2-inactivating mutation stabilizes Spt5 phosphorylation (pSpt5) on chromatin, promotes transcription beyond the normal termination zone detected by precision run-on transcription and sequencing (PRO-seq)6, and is suppressed by ablation of Cdk9 target sites in Spt5. These results support a model whereby the transition of Pol II from elongation to termination is regulated by opposing activities of Cdk9 and Dis2 towards their common substrate Spt5—a bistable switch analogous to a Cdk1-PP1 module that controls mitotic progression4.

Identification of rpo30, a vaccinia virus RNA polymerase gene with structural similarity to a eucaryotic transcription elongation factor

1990 ◽  
Vol 10 (10) ◽  
pp. 5433-5441
Author(s):  
B Y Ahn ◽  
P D Gershon ◽  
E V Jones ◽  
B Moss
Keyword(s):  
Rna Polymerase ◽  
Vaccinia Virus ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
Viral Rna ◽  
In Vitro Translation ◽  
Virus Protein ◽  
Transcriptional Elongation

Eucaryotic transcription factors that stimulate RNA polymerase II by increasing the efficiency of elongation of specifically or randomly initiated RNA chains have been isolated and characterized. We have identified a 30-kilodalton (kDa) vaccinia virus-encoded protein with apparent homology to SII, a 34-kDa mammalian transcriptional elongation factor. In addition to amino acid sequence similarities, both proteins contain C-terminal putative zinc finger domains. Identification of the gene, rpo30, encoding the vaccinia virus protein was achieved by using antibody to the purified viral RNA polymerase for immunoprecipitation of the in vitro translation products of in vivo-synthesized early mRNA selected by hybridization to cloned DNA fragments of the viral genome. Western immunoblot analysis using antiserum made to the vaccinia rpo30 protein expressed in bacteria indicated that the 30-kDa protein remains associated with highly purified viral RNA polymerase. Thus, the vaccinia virus protein, unlike its eucaryotic homolog, is an integral RNA polymerase subunit rather than a readily separable transcription factor. Further studies showed that the expression of rpo30 is regulated by dual early and later promoters.

Genetic interaction between transcription elongation factor TFIIS and RNA polymerase II

1992 ◽  
Vol 12 (9) ◽  
pp. 4142-4152
Author(s):  
J Archambault ◽  
F Lacroute ◽  
A Ruet ◽  
J D Friesen
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Structural Integrity ◽  
Genetic Interaction ◽  
Elongation Factor ◽  
Chemical Mutagenesis ◽  
Yeast Genome ◽  
Transcript Elongation

Little is known about the regions of RNA polymerase II (RNAPII) that are involved in the process of transcript elongation and interaction with elongation factors. One elongation factor, TFIIS, stimulates transcript elongation by binding to RNAPII and facilitating its passage through intrinsic pausing sites in vitro. In Saccharomyces cerevisiae, TFIIS is encoded by the PPR2 gene. Deletion of PPR2 from the yeast genome is not lethal but renders cells sensitive to the uracil analog 6-azauracil (6AU). Here, we show that mutations conferring 6AU sensitivity can also be isolated in the gene encoding the largest subunit of S. cerevisiae RNAPII (RPO21). A screen for mutations in RPO21 that confer 6AU sensitivity identified seven mutations that had been generated by either linker-insertion or random chemical mutagenesis. All seven mutational alterations are clustered within one region of the largest subunit that is conserved among eukaryotic RNAPII. The finding that six of the seven rpo21 mutants failed to grow at elevated temperature underscores the importance of this region for the functional and/or structural integrity of RNAPII. We found that the 6AU sensitivity of the rpo21 mutants can be suppressed by increasing the dosage of the wild-type PPR2 gene, presumably as a result of overexpression of TFIIS. These results are consistent with the proposal that in the rpo21 mutants, the formation of the RNAPII-TFIIS complex is rate limiting for the passage of the mutant enzyme through pausing sites. In addition to implicating a region of the largest subunit of RNAPII in the process of transcript elongation, our observations provide in vivo evidence that TFIIS is involved in transcription by RNAPII.

scholarly journals Mutations in RNA Polymerase II and Elongation Factor SII Severely Reduce mRNA Levels in Saccharomyces cerevisiae

1998 ◽  
Vol 18 (10) ◽  
pp. 5771-5779 ◽  
Author(s):  
J. Cale Lennon ◽  
Megan Wind ◽  
Laura Saunders ◽  
M. Benjamin Hock ◽  
Daniel Reines
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Genetic Interaction ◽  
Elongation Factor ◽  
Mrna Levels ◽  
Wild Type ◽  
Mutant Cells ◽  
Rna Levels

ABSTRACT Elongation factor SII interacts with RNA polymerase II and enables it to transcribe through arrest sites in vitro. The set of genes dependent upon SII function in vivo and the effects on RNA levels of mutations in different components of the elongation machinery are poorly understood. Using yeast lacking SII and bearing a conditional allele of RPB2, the gene encoding the second largest subunit of RNA polymerase II, we describe a genetic interaction between SII and RPB2. An SII gene disruption or therpb2-10 mutation, which yields an arrest-prone enzyme in vitro, confers sensitivity to 6-azauracil (6AU), a drug that depresses cellular nucleoside triphosphates. Cells with both mutations had reduced levels of total poly(A)+ RNA and specific mRNAs and displayed a synergistic level of drug hypersensitivity. In cells in which the SII gene was inactivated, rpb2-10 became dominant, as if template-associated mutant RNA polymerase II hindered the ability of wild-type polymerase to transcribe. Interestingly, while 6AU depressed RNA levels in both wild-type and mutant cells, wild-type cells reestablished normal RNA levels, whereas double-mutant cells could not. This work shows the importance of an optimally functioning elongation machinery for in vivo RNA synthesis and identifies an initial set of candidate genes with which SII-dependent transcription can be studied.

scholarly journals Identification of rpo30, a vaccinia virus RNA polymerase gene with structural similarity to a eucaryotic transcription elongation factor.

1990 ◽  
Vol 10 (10) ◽  
pp. 5433-5441 ◽  
Author(s):  
B Y Ahn ◽  
P D Gershon ◽  
E V Jones ◽  
B Moss
Keyword(s):  
Rna Polymerase ◽  
Vaccinia Virus ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
Viral Rna ◽  
In Vitro Translation ◽  
Virus Protein ◽  
Transcriptional Elongation

Eucaryotic transcription factors that stimulate RNA polymerase II by increasing the efficiency of elongation of specifically or randomly initiated RNA chains have been isolated and characterized. We have identified a 30-kilodalton (kDa) vaccinia virus-encoded protein with apparent homology to SII, a 34-kDa mammalian transcriptional elongation factor. In addition to amino acid sequence similarities, both proteins contain C-terminal putative zinc finger domains. Identification of the gene, rpo30, encoding the vaccinia virus protein was achieved by using antibody to the purified viral RNA polymerase for immunoprecipitation of the in vitro translation products of in vivo-synthesized early mRNA selected by hybridization to cloned DNA fragments of the viral genome. Western immunoblot analysis using antiserum made to the vaccinia rpo30 protein expressed in bacteria indicated that the 30-kDa protein remains associated with highly purified viral RNA polymerase. Thus, the vaccinia virus protein, unlike its eucaryotic homolog, is an integral RNA polymerase subunit rather than a readily separable transcription factor. Further studies showed that the expression of rpo30 is regulated by dual early and later promoters.

scholarly journals Genetic interaction between transcription elongation factor TFIIS and RNA polymerase II.

1992 ◽  
Vol 12 (9) ◽  
pp. 4142-4152 ◽  
Author(s):  
J Archambault ◽  
F Lacroute ◽  
A Ruet ◽  
J D Friesen
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Structural Integrity ◽  
Genetic Interaction ◽  
Elongation Factor ◽  
Chemical Mutagenesis ◽  
Yeast Genome ◽  
Transcript Elongation

Little is known about the regions of RNA polymerase II (RNAPII) that are involved in the process of transcript elongation and interaction with elongation factors. One elongation factor, TFIIS, stimulates transcript elongation by binding to RNAPII and facilitating its passage through intrinsic pausing sites in vitro. In Saccharomyces cerevisiae, TFIIS is encoded by the PPR2 gene. Deletion of PPR2 from the yeast genome is not lethal but renders cells sensitive to the uracil analog 6-azauracil (6AU). Here, we show that mutations conferring 6AU sensitivity can also be isolated in the gene encoding the largest subunit of S. cerevisiae RNAPII (RPO21). A screen for mutations in RPO21 that confer 6AU sensitivity identified seven mutations that had been generated by either linker-insertion or random chemical mutagenesis. All seven mutational alterations are clustered within one region of the largest subunit that is conserved among eukaryotic RNAPII. The finding that six of the seven rpo21 mutants failed to grow at elevated temperature underscores the importance of this region for the functional and/or structural integrity of RNAPII. We found that the 6AU sensitivity of the rpo21 mutants can be suppressed by increasing the dosage of the wild-type PPR2 gene, presumably as a result of overexpression of TFIIS. These results are consistent with the proposal that in the rpo21 mutants, the formation of the RNAPII-TFIIS complex is rate limiting for the passage of the mutant enzyme through pausing sites. In addition to implicating a region of the largest subunit of RNAPII in the process of transcript elongation, our observations provide in vivo evidence that TFIIS is involved in transcription by RNAPII.

scholarly journals Elongin A regulates transcription in vivo through enhanced RNA polymerase processivity

2020 ◽  
pp. jbc.RA120.015876
Author(s):  
Yating Wang ◽  
Liming Hou ◽  
M. Behfar Ardehali ◽  
Robert E. Kingston ◽  
Brian D Dynlacht
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcriptional Elongation ◽  
Rna Seq ◽  
Transcription Profiles ◽  
Genome Wide ◽  
The Impact

Elongin is an RNA polymerase II (RNAPII)-associated factor that has been shown to stimulate transcriptional elongation in vitro. The Elongin complex is thought to be required for transcriptional induction in response to cellular stimuli and to ubiquitinate RNAPII in response to DNA damage. Yet the impact of the Elongin complex on transcription in vivo has not been well studied. Here, we performed comprehensive studies of the role of Elongin A, the largest subunit of the Elongin complex, on RNAPII transcription genome-wide. Our results suggest that Elongin A localizes to actively transcribed regions and potential enhancers, and the level of recruitment correlated with transcription levels. We also identified a large group of factors involved in transcription as Elongin A-associated factors. In addition, we found that loss of Elongin A leads to dramatically reduced levels of Ser2-phosphorylated, but not total, RNAPII, and cells depleted of Elongin A show stronger promoter RNAPII pausing, suggesting that Elongin A may be involved in the release of paused RNAPII. Our RNA-seq studies suggest that loss of Elongin A did not alter global transcription, and unlike prior in vitro studies, we did not observe a dramatic impact on RNAPII elongation rates in our cell-based nascent RNA-seq experiments upon Elongin A depletion. Taken together, our studies provide the first comprehensive analysis of the role of Elongin A in regulating transcription in vivo. Our studies also revealed that unlike prior in vitro findings, depletion of Elongin A has little impact on global transcription profiles and transcription elongation in vivo.

scholarly journals Spt4 Facilitates the Movement of RNA Polymerase II through the +2 Nucleosomal Barrier

2021 ◽  
Author(s):  
Ülkü Uzun ◽  
Thomas Brown ◽  
Harry Fischl ◽  
Andrew Angel ◽  
Jane Mellor
Keyword(s):  
Saccharomyces Cerevisiae ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
Nucleosome Positioning ◽  
Gene Body ◽  
Precise Position ◽  
Transcription Elongation Factor

AbstractSpt4 is a transcription elongation factor, with homologues in organisms with nucleosomes. Structural and in vitro studies implicate Spt4 in transcription through nucleosomes, yet the in vivo function of Spt4 is unclear. Here we assessed the precise position of Spt4 during transcription and the consequences of loss of Spt4 on RNA polymerase II (RNAPII) dynamics and nucleosome positioning in Saccharomyces cerevisiae. In the absence of Spt4, the spacing between gene-body nucleosomes increases and RNAPII accumulates upstream of the nucleosomal dyad, most dramatically at nucleosome +2. Spt4 associates with elongating RNAPII early in transcription and its association dynamically changes depending on nucleosome positions. Together, our data show that Spt4 regulates early elongation dynamics, participates in co-transcriptional nucleosome positioning, and promotes RNAPII movement through the gene-body nucleosomes, especially the +2 nucleosome.

scholarly journals TFIIH-Associated Cdk7 Kinase Functions in Phosphorylation of C-Terminal Domain Ser7 Residues, Promoter-Proximal Pausing, and Termination by RNA Polymerase II

2009 ◽  
Vol 29 (20) ◽  
pp. 5455-5464 ◽  
Author(s):  
Kira Glover-Cutter ◽  
Stéphane Larochelle ◽  
Benjamin Erickson ◽  
Chao Zhang ◽  
Kevan Shokat ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Elongation Factor ◽  
Histone H4 ◽  
Pol Ii ◽  
Terminal Domain ◽  
Histone H4 Acetylation ◽  
Flanking Regions

ABSTRACT The function of human TFIIH-associated Cdk7 in RNA polymerase II (Pol II) transcription and C-terminal domain (CTD) phosphorylation was investigated in analogue-sensitive Cdk7 as/as mutant cells where the kinase can be inhibited without disrupting TFIIH. We show that both Cdk7 and Cdk9/PTEFb contribute to phosphorylation of Pol II CTD Ser5 residues on transcribed genes. Cdk7 is also a major kinase of CTD Ser7 on Pol II at the c-fos and U snRNA genes. Furthermore, TFIIH and recombinant Cdk7-CycH-Mat1 as well as recombinant Cdk9-CycT1 phosphorylated CTD Ser7 and Ser5 residues in vitro. Inhibition of Cdk7 in vivo suppressed the amount of Pol II accumulated at 5′ ends on several genes including c-myc, p21, and glyceraldehyde-3-phosphate dehydrogenase genes, indicating reduced promoter-proximal pausing or polymerase “leaking” into the gene. Consistent with a 5′ pausing defect, Cdk7 inhibition reduced recruitment of the negative elongation factor NELF at start sites. A role of Cdk7 in regulating elongation is further suggested by enhanced histone H4 acetylation and diminished histone H4 trimethylation on lysine 36—two marks of elongation—within genes when the kinase was inhibited. Consistent with a new role for TFIIH at 3′ ends, it was detected within genes and 3′-flanking regions, and Cdk7 inhibition delayed pausing and transcription termination.

Sign in / Sign up

Export Citation Format

Share Document