Termination and pausing of RNA polymerase II downstream of yeast polyadenylation sites

Little is known about the transcriptional events which occur downstream of polyadenylation sites. Although the polyadenylation site of a gene can be easily identified, it has been difficult to determine the site of transcription termination in vivo because of the rapid processing of pre-mRNAs. Using an in vitro approach, we have shown that sequences from the 3' ends of two different Saccharomyces cerevisiae genes, ADH2 and GAL7, direct transcription termination and/or polymerase pausing in yeast nuclear extracts. In the case of the ADH2 sequence, the RNA synthesized in vitro ends approximately 50 to 150 nucleotides downstream of the poly(A) site. This RNA is not polyadenylated and may represent the primary transcript. A similarly sized nonpolyadenylated [poly(A)-] transcript can be detected in vivo from the same transcriptional template. A GAL7 template also directs the in vitro synthesis of an RNA which extends a short distance past the poly(A) site. However, a significant amount of the GAL7 RNA is polyadenylated at or close to the in vivo poly(A) site. Mutations of GAL7 or ADH2 poly(A) signals prevent polyadenylation but do not affect the in vitro synthesis of the extended poly(A)- transcript. Since transcription of the mutant template continues through this region in vivo, it is likely that a strong RNA polymerase II pause site lies within the 3'-end sequences. Our data support the hypothesis that the coupling of this pause site to a functional polyadenylation signal results in transcription termination.

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Transcription termination at the chicken beta H-globin gene

Molecular and Cellular Biology ◽

10.1128/mcb.8.12.5369-5377.1988 ◽

1988 ◽

Vol 8 (12) ◽

pp. 5369-5377

Author(s):

T M Pribyl ◽

H G Martinson

Keyword(s):

Rna Polymerase Ii ◽

Inverted Repeat ◽

Transcription Termination ◽

Globin Gene ◽

H Gene ◽

Delta G ◽

A Site ◽

Cat Expression

We characterized the transcription termination region of the chicken beta H-globin gene. First we located the region by nuclear runon transcription in vitro. Then we sequenced and subcloned it into a chloramphenicol acetyltransferase (CAT) expression vector for assay in vivo. The region of beta H termination contains two interesting elements located about 1 kilobase downstream of the beta H gene poly(A) site. Either element alone can block CAT expression if inserted between the promoter and the poly(A) site of the cat gene in pRSVcat. The first element in the termination region is an unusually large inverted repeat in the DNA (delta G = -71 kcal). The second element, 200 base pairs further downstream, is an RNA polymerase II promoter which directs transcription back upstream on the complementary strand. This transcription converges on and collides with that from the beta H gene at or near the inverted repeat where transcription from both directions stops. We propose that the inverted repeat is a strong pause site which positions the converging polymerases for mutual site-specific termination.

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Mechanism of Poly(A) Signal Transduction to RNA Polymerase II In Vitro

Molecular and Cellular Biology ◽

10.1128/mcb.21.21.7495-7508.2001 ◽

2001 ◽

Vol 21 (21) ◽

pp. 7495-7508 ◽

Cited By ~ 20

Author(s):

Dong P. Tran ◽

Steven J. Kim ◽

Noh Jin Park ◽

Tiffany M. Jew ◽

Harold G. Martinson

Keyword(s):

Signal Transduction ◽

Rna Polymerase ◽

Rna Polymerase Ii ◽

Nuclear Extract ◽

Signaling Mechanism ◽

A Cell ◽

A Site ◽

Crude Nuclear Extract

ABSTRACT Termination of transcription by RNA polymerase II usually requires the presence of a functional poly(A) site. How the poly(A) site signals its presence to the polymerase is unknown. All models assume that the signal is generated after the poly(A) site has been extruded from the polymerase, but this has never been tested experimentally. It is also widely accepted that a “pause” element in the DNA stops the polymerase and that cleavage at the poly(A) site then signals termination. These ideas also have never been tested. The lack of any direct tests of the poly(A) signaling mechanism reflects a lack of success in reproducing the poly(A) signaling phenomenon in vitro. Here we describe a cell-free transcription elongation assay that faithfully recapitulates poly(A) signaling in a crude nuclear extract. The assay requires the use of citrate, an inhibitor of RNA polymerase II carboxyl-terminal domain phosphorylation. Using this assay we show the following. (i) Wild-type but not mutant poly(A) signals instruct the polymerase to stop transcription on downstream DNA in a manner that parallels true transcription termination in vivo. (ii) Transcription stops without the need of downstream elements in the DNA. (iii)cis-antisense inhibition blocks signal transduction, indicating that the signal to stop transcription is generated following extrusion of the poly(A) site from the polymerase. (iv) Signaling can be uncoupled from processing, demonstrating that signaling does not require cleavage at the poly(A) site.

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Transcription termination at the chicken beta H-globin gene.

Molecular and Cellular Biology ◽

10.1128/mcb.8.12.5369 ◽

1988 ◽

Vol 8 (12) ◽

pp. 5369-5377 ◽

Cited By ~ 14

Author(s):

T M Pribyl ◽

H G Martinson

Keyword(s):

Rna Polymerase Ii ◽

Inverted Repeat ◽

Transcription Termination ◽

Globin Gene ◽

H Gene ◽

Delta G ◽

A Site ◽

Cat Expression

We characterized the transcription termination region of the chicken beta H-globin gene. First we located the region by nuclear runon transcription in vitro. Then we sequenced and subcloned it into a chloramphenicol acetyltransferase (CAT) expression vector for assay in vivo. The region of beta H termination contains two interesting elements located about 1 kilobase downstream of the beta H gene poly(A) site. Either element alone can block CAT expression if inserted between the promoter and the poly(A) site of the cat gene in pRSVcat. The first element in the termination region is an unusually large inverted repeat in the DNA (delta G = -71 kcal). The second element, 200 base pairs further downstream, is an RNA polymerase II promoter which directs transcription back upstream on the complementary strand. This transcription converges on and collides with that from the beta H gene at or near the inverted repeat where transcription from both directions stops. We propose that the inverted repeat is a strong pause site which positions the converging polymerases for mutual site-specific termination.

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Functional dissection of the catalytic mechanism of mammalian RNA polymerase II

Biochemistry and Cell Biology ◽

10.1139/o05-061 ◽

2005 ◽

Vol 83 (4) ◽

pp. 497-504 ◽

Cited By ~ 2

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.

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Direct Interaction between the Subunit RAP30 of Transcription Factor IIF (TFIIF) and RNA Polymerase Subunit 5, Which Contributes to the Association between TFIIF and RNA Polymerase II

Journal of Biological Chemistry ◽

10.1074/jbc.m009634200 ◽

2001 ◽

Vol 276 (15) ◽

pp. 12266-12273 ◽

Cited By ~ 31

Author(s):

Wenxiang Wei ◽

Dorjbal Dorjsuren ◽

Yong Lin ◽

Weiping Qin ◽

Takahiro Nomura ◽

...

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Middle Part ◽

Wild Type ◽

Binding Region ◽

Pol Ii ◽

Transcription Factor Iif ◽

B Virus

The general transcription factor IIF (TFIIF) assembled in the initiation complex, and RAP30 of TFIIF, have been shown to associate with RNA polymerase II (pol II), although it remains unclear which pol II subunit is responsible for the interaction. We examined whether TFIIF interacts with RNA polymerase II subunit 5 (RPB5), the exposed domain of which binds transcriptional regulatory factors such as hepatitis B virus X protein and a novel regulatory protein, RPB5-mediating protein. The results demonstrated that RPB5 directly binds RAP30in vitrousing purified recombinant proteins andin vivoin COS1 cells transiently expressing recombinant RAP30 and RPB5. The RAP30-binding region was mapped to the central region (amino acids (aa) 47–120) of RPB5, which partly overlaps the hepatitis B virus X protein-binding region. Although the middle part (aa 101–170) and the N-terminus (aa 1–100) of RAP30 independently bound RPB5, the latter was not involved in the RPB5 binding when RAP30 was present in TFIIF complex. Scanning of the middle part of RAP30 by clustered alanine substitutions and then point alanine substitutions pinpointed two residues critical for the RPB5 binding inin vitroandin vivoassays. Wild type but not mutants Y124A and Q131A of RAP30 coexpressed with FLAG-RAP74 efficiently recovered endogenous RPB5 to the FLAG-RAP74-bound anti-FLAG M2 resin. The recovered endogenous RPB5 is assembled in pol II as demonstrated immunologically. Interestingly, coexpression of the central region of RPB5 and wild type RAP30 inhibited recovery of endogenous pol II to the FLAG-RAP74-bound M2 resin, strongly suggesting that the RAP30-binding region of RPB5 inhibited the association of TFIIF and pol II. The exposed domain of RPB5 interacts with RAP30 of TFIIF and is important for the association between pol II and TFIIF.

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An RNA Polymerase Pause Site Is Associated with the Immunoglobulin μs Poly(A) Site

Molecular and Cellular Biology ◽

10.1128/mcb.22.15.5606-5615.2002 ◽

2002 ◽

Vol 22 (15) ◽

pp. 5606-5615 ◽

Cited By ~ 27

Author(s):

Martha L. Peterson ◽

Shannon Bertolino ◽

Frankie Davis

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Rna Processing ◽

Immunoglobulin A ◽

Expression Ratio ◽

B Cell Maturation ◽

Mrna Ratio ◽

Site Use ◽

A Site ◽

Pause Site

ABSTRACT Immunoglobulin μ alternative RNA processing is regulated during B-cell maturation and requires balanced efficiencies of the competing splice (μm) and cleavage-polyadenylation (μs) reactions. When we deleted sequences 50 to 200 nucleotides beyond the μs poly(A) site, the μs/μm mRNA ratio decreased three- to eightfold in B, plasma, and nonlymphoid cells. The activity could not be localized to a smaller fragment but did function in heterologous contexts. Our data suggest that this region contains an RNA polymerase II pause site that enhances the use of the μs poly(A) site. First, known pause sites replaced the activity of the deleted fragment. Second, the μ fragment, when placed between tandem poly(A) sites, enhanced the use of the upstream poly(A) site. Finally, nuclear run-ons detected an increase in RNA polymerase loading just downstream from the μs poly(A) site, even when the poly(A) site was inactivated. When this μ fragment and another pause site were inserted 1 kb downstream from the μs poly(A) site, they no longer affected the mRNA expression ratio, suggesting that pause sites affect poly(A) site use over a limited distance. Fragments from the immunoglobulin A gene were also found to have RNA polymerase pause site activity.

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

Molecular and Cellular Biology ◽

10.1128/mcb.10.10.5433-5441.1990 ◽

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.

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In vitro analysis of a transcription termination site for RNA polymerase II.

Molecular and Cellular Biology ◽

10.1128/mcb.10.11.5782 ◽

1990 ◽

Vol 10 (11) ◽

pp. 5782-5795 ◽

Cited By ~ 19

Author(s):

D K Wiest ◽

D K Hawley

Keyword(s):

Rna Polymerase ◽

Rna Polymerase Ii ◽

Dna Sequences ◽

Nuclear Extract ◽

Transcription Unit ◽

Dependent Manner ◽

Wide Range ◽

Vitro Analysis

Transcription from the adenovirus major late (ML) promoter has previously been shown to pause or terminate prematurely in vivo and in vitro at a site within the first intron of the major late transcription unit. We are studying the mechanism of elongation arrest at this site in vitro to define the DNA sequences and proteins that determine the elongation behavior of RNA polymerase II. Our assay system consists of a nuclear extract prepared from cultured human cells. With standard reaction conditions, termination is not observed downstream of the ML promoter. However, in the presence of Sarkosyl, up to 80% of the transcripts terminate 186 nucleotides downstream of the start site. Using this assay, we showed that the DNA sequences required to promote maximal levels of termination downstream of the ML promoter reside within a 65-base-pair region and function in an orientation-dependent manner. To test whether elongation complexes from the ML promoter were functionally homogeneous, we determined the termination efficiency at each of two termination sites placed in tandem. We found that the behavior of the elongation complexes was different at these sites, with termination being greater at the downstream site over a wide range of Sarkosyl concentrations. This result ruled out a model in which the polymerases that read through the first site were stably modified to antiterminate. We also demonstrated that the ability of the elongation complexes to respond to the ML termination site was promoter specific, as the site did not function efficiently downstream of a heterologous promoter. Taken together, the results presented here are not consistent with the simplest class of models that have been proposed previously for the mechanism of Sarkosyl-induced termination.

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