Transcription termination at the chicken beta H-globin gene

1988 ◽  
Vol 8 (12) ◽  
pp. 5369-5377
Author(s):  
T M Pribyl ◽  
H G Martinson

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.

1988 ◽  
Vol 8 (12) ◽  
pp. 5369-5377 ◽  
Author(s):  
T M Pribyl ◽  
H G Martinson

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.


1993 ◽  
Vol 13 (9) ◽  
pp. 5159-5167
Author(s):  
L E Hyman ◽  
C L Moore

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.


1993 ◽  
Vol 13 (9) ◽  
pp. 5159-5167 ◽  
Author(s):  
L E Hyman ◽  
C L Moore

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.


1997 ◽  
Vol 69 (2) ◽  
pp. 101-110 ◽  
Author(s):  
ALAN TAYLOR ◽  
LIQUN ZHANG ◽  
JOHN HERRMANN ◽  
BEI WU ◽  
LARRY KEDES ◽  
...  

In vitro studies using highly purified calf thymus RNA polymerase II and a fragment spanning the first intron of H3.3 as template DNA have demonstrated the existence of a strong transcription termination site consisting of thymidine stretches. In this study, nuclear run-on experiments have been performed to assess the extent to which transcription elongation is blocked in vivo using DNA probes corresponding to regions 5′ and 3′ of the in vitro termination sites. These studies suggest that H3.3 expression is stimulated following the inhibition of DNA synthesis through the elimination of the transcription elongation block. Interestingly, both the in vivo and in vitro experiments have revealed that the transcriptional block/termination sites are positioned immediately downstream of a 73 bp region that has been over 90% conserved between the chicken and human H3.3 genes. The extreme conservation of this intronic region suggests a possible role in maintaining cis-acting function. Electrophoretic mobility shift experiments show that HeLa cell nuclear extracts contain protein factors that bind specifically to the region of transcription elongation block. Furthermore, we demonstrate a correlation between the protein binding activity and the transcriptional block in cells that have been either arrested at the initiation of S phase or were replication-interrupted by hydroxyurea. DNA footprinting experiments indicate that the region of protein binding is at the 3′ end of the conserved region and overlaps with one of the three in-vitro-mapped termination sites.


2021 ◽  
Author(s):  
Jie Li ◽  
Lei Yue ◽  
Wenting Zhang ◽  
Zhihua Li ◽  
Bing Zhang ◽  
...  

Recently, aCPSF1 was reported to function as the long-sought global transcription termination factor of archaea, while the working mechanism remains elusive. This work, through analyzing transcript-3′end-sequencing data of Methanococcus maripaludis, found positive correlations of both the terminator uridine(U)-tract and aCPSF1 with hierarchical transcription termination efficiencies (TTEs) at the genome-wide level. In vitro assays determined that aCPSF1 specifically binds to the terminator U-tract with U-tract number-related binding abilities, and in vivo assays demonstrated the two are indispensable in dictating high TTEs, revealing that aCPSF1 and the terminator U-tract in synergy determine high TTEs. The N-terminal KH domains equip aCPSF1 of specific binding to terminator U-tract and the in vivo aCPSF1-terminator U-tract synergism; aCPSF1's nuclease activity was also required for TTEs. aCPSF1 also functioned as back-up termination for transcripts with weak intrinsic terminator signals. aCPSF1 orthologs from Lokiarchaeota and Thaumarchaeota exhibited similar U-tract synergy in dictating TTEs. Therefore, aCPSF1 and the intrinsic U-rich terminator could work in a noteworthy two-in-one termination mode in Archaea, which could be widely employed by archaeal phyla; using one factor recognizing U-rich terminator signal and cleaving transcript 3′-end, the archaeal aCPSF1-dependent transcription termination could display a simplified archetypal mode of the eukaryotic RNA polymerase II termination machinery.


eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Jie Li ◽  
Lei Yue ◽  
Zhihua Li ◽  
Wenting Zhang ◽  
Bing Zhang ◽  
...  

Recently, aCPSF1 was reported to function as the long-sought global transcription termination factor of archaea; however, the working mechanism remains elusive. This work, through analyzing transcript-3′end-sequencing data of Methanococcus maripaludis, found genome-wide positive correlations of both the terminator uridine(U)-tract and aCPSF1 with hierarchical transcription termination efficacies (TTEs). In vitro assays determined that aCPSF1 specifically binds to the terminator U-tract with U-tract number-related binding affinity, and in vivo assays demonstrated the two elements are indispensable in dictating high TTEs, revealing that aCPSF1 and the terminator U-tract cooperatively determine high TTEs. The N-terminal KH domains equip aCPSF1 with specific-binding capacity to terminator U-tract and the aCPSF1-terminator U-tract cooperation; while the nuclease activity of aCPSF1 was also required for TTEs. aCPSF1 also guarantees the terminations of transcripts with weak intrinsic terminator signals. aCPSF1 orthologs from Lokiarchaeota and Thaumarchaeota exhibited similar U-tract cooperation in dictating TTEs. Therefore, aCPSF1 and the intrinsic U-rich terminator could work in a noteworthy two-in-one termination mode in archaea, which may be widely employed by archaeal phyla; using one trans-action factor to recognize U-rich terminator signal and cleave transcript 3′-end, the archaeal aCPSF1-dependent transcription termination may represent a simplified archetypal mode of the eukaryotic RNA polymerase II termination machinery.


2001 ◽  
Vol 21 (21) ◽  
pp. 7495-7508 ◽  
Author(s):  
Dong P. Tran ◽  
Steven J. Kim ◽  
Noh Jin Park ◽  
Tiffany M. Jew ◽  
Harold G. Martinson

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.


1985 ◽  
Vol 5 (1) ◽  
pp. 147-160
Author(s):  
M L Rohrbaugh ◽  
J E Johnson ◽  
M D James ◽  
R C Hardison

We have hybridized pulse-labeled nuclear transcripts to cloned DNA fragments from the rabbit beta-like globin genes to determine the developmental timing, extent, and asymmetry of their transcription. The fetal-adult gene beta 1 was transcribed in fetal liver but not embryonic nuclei, whereas genes beta 3 and beta 4, which encode embryonic globin polypeptides, were transcribed only in embryonic nuclei. This shows that the switch from embryonic to fetal-adult globin production in rabbits is accomplished primarily by differential transcription of the beta-like globin genes. Gene beta 1 was subdivided into M13 subclones and tested for hybridization to nascent RNA. The nucleotide sequence of the 3' flanking region of gene beta 1 was also determined for 2,447 base pairs past the polyadenylation [poly(A)] site. No transcripts were found 5' to the cap site, but asymmetric transcription of gene beta 1 proceeded at a high level through the gene and past the poly(A) addition site for 603 nucleotides. The level of transcription declined after this, gradually dropping through the next 568 nucleotides. No polymerases were found on a fragment that begins 1,707 nucleotides past the poly(A) site; this fragment was part of a segment of repetitive DNA. These data show that the transcription unit of gene beta 1 begins at or near the cap nucleotide and extends at least 1,171 but no more than 1,706 nucleotides past the poly(A) addition site. The DNA segment that precedes the region of declining transcription contained an inverted repeat and encoded a short RNA transcribed by RNA polymerase II from the strand opposite the beta 1 transcript. These two features may function to attenuate the transcription of gene beta 1. An inverted repeat and a potential polymerase II transcription unit were also found in the homologous segment 3' to the human beta-globin gene. A short DNA segment close to the 3' end of the beta 1 transcription unit was transcribed more actively than the surrounding DNA, and it contained sequences that match the consensus internal control region for RNA polymerase III. This DNA segment may contain a separate polymerase III transcription unit. A member of the D repeat family located 3' to gene beta 1 was not transcribed in its entirety coordinately with beta 1.


1985 ◽  
Vol 5 (1) ◽  
pp. 147-160 ◽  
Author(s):  
M L Rohrbaugh ◽  
J E Johnson ◽  
M D James ◽  
R C Hardison

We have hybridized pulse-labeled nuclear transcripts to cloned DNA fragments from the rabbit beta-like globin genes to determine the developmental timing, extent, and asymmetry of their transcription. The fetal-adult gene beta 1 was transcribed in fetal liver but not embryonic nuclei, whereas genes beta 3 and beta 4, which encode embryonic globin polypeptides, were transcribed only in embryonic nuclei. This shows that the switch from embryonic to fetal-adult globin production in rabbits is accomplished primarily by differential transcription of the beta-like globin genes. Gene beta 1 was subdivided into M13 subclones and tested for hybridization to nascent RNA. The nucleotide sequence of the 3' flanking region of gene beta 1 was also determined for 2,447 base pairs past the polyadenylation [poly(A)] site. No transcripts were found 5' to the cap site, but asymmetric transcription of gene beta 1 proceeded at a high level through the gene and past the poly(A) addition site for 603 nucleotides. The level of transcription declined after this, gradually dropping through the next 568 nucleotides. No polymerases were found on a fragment that begins 1,707 nucleotides past the poly(A) site; this fragment was part of a segment of repetitive DNA. These data show that the transcription unit of gene beta 1 begins at or near the cap nucleotide and extends at least 1,171 but no more than 1,706 nucleotides past the poly(A) addition site. The DNA segment that precedes the region of declining transcription contained an inverted repeat and encoded a short RNA transcribed by RNA polymerase II from the strand opposite the beta 1 transcript. These two features may function to attenuate the transcription of gene beta 1. An inverted repeat and a potential polymerase II transcription unit were also found in the homologous segment 3' to the human beta-globin gene. A short DNA segment close to the 3' end of the beta 1 transcription unit was transcribed more actively than the surrounding DNA, and it contained sequences that match the consensus internal control region for RNA polymerase III. This DNA segment may contain a separate polymerase III transcription unit. A member of the D repeat family located 3' to gene beta 1 was not transcribed in its entirety coordinately with beta 1.


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