scholarly journals Faculty Opinions recommendation of Comparison of transcriptional initiation by RNA polymerase II across eukaryotic species.

2021 ◽  
Author(s):  
James Coker
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcriptional Initiation ◽  
Eukaryotic Species

scholarly journals Comparison of transcriptional initiation by RNA polymerase II across eukaryotic species

eLife ◽  
2021 ◽  
Vol 10 ◽  
Author(s):  
Natalia Petrenko ◽  
Kevin Struhl
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Initiation Site ◽  
Transcriptional Initiation ◽  
Pol Ii ◽  
Activator Proteins ◽  
General Transcription Factors ◽  
Eukaryotic Species ◽  
Species Specific ◽  
And Function

The preinitiation complex (PIC) for transcriptional initiation by RNA polymerase (Pol) II is composed of general transcription factors that are highly conserved. However, analysis of ChIP-seq datasets reveals kinetic and compositional differences in the transcriptional initiation process among eukaryotic species. In yeast, Mediator associates strongly with activator proteins bound to enhancers, but it transiently associates with promoters in a form that lacks the kinase module. In contrast, in human, mouse, and fly cells, Mediator with its kinase module stably associates with promoters, but not with activator-binding sites. This suggests that yeast and metazoans differ in the nature of the dynamic bridge of Mediator between activators and Pol II and the composition of a stable inactive PIC-like entity. As in yeast, occupancies of TATA-binding protein (TBP) and TBP-associated factors (Tafs) at mammalian promoters are not strictly correlated. This suggests that within PICs, TFIID is not a monolithic entity, and multiple forms of TBP affect initiation at different classes of genes. TFIID in flies, but not yeast and mammals, interacts strongly at regions downstream of the initiation site, consistent with the importance of downstream promoter elements in that species. Lastly, Taf7 and the mammalian-specific Med26 subunit of Mediator also interact near the Pol II pause region downstream of the PIC, but only in subsets of genes and often not together. Species-specific differences in PIC structure and function are likely to affect how activators and repressors affect transcriptional activity.

scholarly journals Functions of the N- and C-Terminal Domains of Human RAP74 in Transcriptional Initiation, Elongation, and Recycling of RNA Polymerase II

1998 ◽  
Vol 18 (4) ◽  
pp. 2130-2142 ◽  
Author(s):  
Lei Lei ◽  
Delin Ren ◽  
Ann Finkelstein ◽  
Zachary F. Burton
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcriptional Initiation ◽  
Pol Ii ◽  
Terminal Domain ◽  
Multiple Round ◽  
Major Late Promoter ◽  
Central Loop ◽  
Transcription Cycle ◽  
Terminal Domains

ABSTRACT Transcription factor IIF (TFIIF) cooperates with RNA polymerase II (pol II) during multiple stages of the transcription cycle including preinitiation complex assembly, initiation, elongation, and possibly termination and recycling. Human TFIIF appears to be an α2β2 heterotetramer of RNA polymerase II-associating protein 74- and 30-kDa subunits (RAP74 and RAP30). From inspection of its 517-amino-acid (aa) sequence, the RAP74 subunit appears to comprise separate N- and C-terminal domains connected by a flexible loop. In this study, we present functional data that strongly support this model for RAP74 architecture and further show that the N- and C-terminal domains and the central loop of RAP74 have distinct roles during separate phases of the transcription cycle. The N-terminal domain of RAP74 (minimally aa 1 to 172) is sufficient to deliver pol II into a complex formed on the adenovirus major late promoter with the TATA-binding protein, TFIIB, and RAP30. A more complete N-terminal domain fragment (aa 1 to 217) strongly stimulates both accurate initiation and elongation by pol II. The region of RAP74 between aa 172 and 205 and a subregion between aa 170 and 178 are critical for both accurate initiation and elongation, and mutations in these regions have similar effects on initiation and elongation. Based on these observations, RAP74 appears to have similar functions in initiation and elongation. The central region and the C-terminal domain of RAP74 do not contribute strongly to single-round accurate initiation or elongation stimulation but do stimulate multiple-round transcription in an extract system.

scholarly journals The RNA Polymerase II Kinase Ctk1 Regulates Positioning of a 5′ Histone Methylation Boundary along Genes

2006 ◽  
Vol 27 (2) ◽  
pp. 721-731 ◽  
Author(s):  
Tiaojiang Xiao ◽  
Yoichiro Shibata ◽  
Bhargavi Rao ◽  
R. Nicholas Laribee ◽  
Rose O'Rourke ◽  
...  
Keyword(s):  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcription Initiation ◽  
Histone Deacetylation ◽  
H3k4 Methylation ◽  
H3k36 Methylation ◽  
Transcriptional Initiation ◽  
Spurious Transcription ◽  
Transcriptional Stress ◽  
Rnap Ii

ABSTRACT In yeast and other eukaryotes, the histone methyltransferase Set1 mediates methylation of lysine 4 on histone H3 (H3K4me). This modification marks the 5′ end of transcribed genes in a 5′-to-3′ tri- to di- to monomethyl gradient and promotes association of chromatin-remodeling and histone-modifying enzymes. Here we show that Ctk1, the serine 2 C-terminal domain (CTD) kinase for RNA polymerase II (RNAP II), regulates H3K4 methylation. We found that CTK1 deletion nearly abolished H3K4 monomethylation yet caused a significant increase in H3K4 di- and trimethylation. Both in individual genes and genome-wide, loss of CTK1 disrupted the H3K4 methylation patterns normally observed. H3K4me2 and H3K4me3 spread 3′ into the bodies of genes, while H3K4 monomethylation was diminished. These effects were dependent on the catalytic activity of Ctk1 but are independent of Set2-mediated H3K36 methylation. Furthermore, these effects are not due to spurious transcription initiation in the bodies of genes, to changes in RNAP II occupancy, to changes in serine 5 CTD phosphorylation patterns, or to “transcriptional stress.” These data show that Ctk1 acts to restrict the spread of H3K4 methylation through a mechanism that is independent of a general transcription defect. The evidence presented suggests that Ctk1 controls the maintenance of suppressive chromatin in the coding regions of genes by both promoting H3K36 methylation, which leads to histone deacetylation, and preventing the 3′ spread of H3K4 trimethylation, a mark associated with transcriptional initiation.

scholarly journals A dual role for H2A.Z.1 in modulating the dynamics of RNA Polymerase II initiation and elongation

2020 ◽  
Author(s):  
Constantine Mylonas ◽  
Alexander L. Auld ◽  
Choongman Lee ◽  
Ibrahim I. Cisse ◽  
Laurie A. Boyer
Keyword(s):  
Gene Expression ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Single Molecule ◽  
Mammalian Cells ◽  
Embryonic Stem ◽  
Super Resolution ◽  
Fine Tuning ◽  
Transcriptional Initiation ◽  
Single Molecule Level

AbstractRNAPII pausing immediately downstream of the transcription start site (TSS) is a critical rate limiting step at most metazoan genes that allows fine-tuning of gene expression in response to diverse signals1–5. During pause-release, RNA Polymerase II (RNAPII) encounters an H2A.Z.1 nucleosome6–8, yet how this variant contributes to transcription is poorly understood. Here, we use high resolution genomic approaches2,9 (NET-seq and ChIP-nexus) along with live cell super-resolution microscopy (tcPALM)10 to investigate the role of H2A.Z.1 on RNAPII dynamics in embryonic stem cells (ESCs). Using a rapid, inducible protein degron system11 combined with transcriptional initiation and elongation inhibitors, our quantitative analysis shows that H2A.Z.1 slows the release of RNAPII, impacting both RNAPII and NELF dynamics at a single molecule level. We also find that H2A.Z.1 loss has a dramatic impact on nascent transcription at stably paused, signal-dependent genes. Furthermore, we demonstrate that H2A.Z.1 inhibits re-assembly and re-initiation of the PIC to reinforce the paused state and acts as a strong additional pause signal at stably paused genes. Together, our study suggests that H2A.Z.1 fine-tunes gene expression by regulating RNAPII kinetics in mammalian cells.

scholarly journals A region internal to the coding sequences is essential for transcription of the yeast Ty-D15 element.

1989 ◽  
Vol 9 (9) ◽  
pp. 3667-3678 ◽  
Author(s):  
K Yu ◽  
R T Elder
Keyword(s):  
Rna Polymerase ◽  
Transposable Element ◽  
Rna Polymerase Ii ◽  
Initiation Site ◽  
Direct Repeats ◽  
Yeast Gene ◽  
Base Pairs ◽  
Transcriptional Initiation ◽  
Coding Sequences ◽  
Transcription Signals

The major transcript of the yeast transposable element Ty1 has its 5' end in one delta and the 3' end in the opposite delta, the direct repeats of about 335 base pairs (bp) at each end of the element. The transcriptional initiation signals of the Ty-D15 element that give rise to this transcript were found to have a number of unusual characteristics. The 5' delta by itself, which contained the initiation site for Ty transcription, gave no detectable transcription. A region internal to the transcript in a translated part of the element and about 140 bp downstream of the 5' delta was essential for initiation of the major Ty transcript. This internal activating region (IAR) had several interesting properties. When the portion of the delta upstream of the initiation site was replaced with DNA fragments that did not by themselves act as promoters, initiation directed by the IAR still occurred at about the same position, 200 to 400 bp upstream of the IAR. If fragments containing the IAR were inverted, transcription could still occur. When 468 or 636 bp was inserted between the delta and the IAR, initiations occurred near the normal delta initiation site and in the inserted DNA. Therefore, the location and properties of transcription signals for Ty-D15 differ considerably from those expected for a yeast gene transcribed by RNA polymerase II.

scholarly journals In vivo binding of NF-κB to the IκBβ promoter is insufficient for transcriptional activation

2006 ◽  
Vol 400 (1) ◽  
pp. 115-125 ◽  
Author(s):  
Bryan D. Griffin ◽  
Paul N. Moynagh
Keyword(s):  
Gene Regulation ◽  
Transcription Factor ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcriptional Activation ◽  
Nuclear Factor Κb ◽  
Transcriptional Initiation ◽  
Il Interleukin

Despite certain structural and biochemical similarities, differences exist in the function of the NF-κB (nuclear factor κB) inhibitory proteins IκBα (inhibitory κBα) and IκBβ. The functional disparity arises in part from variance at the level of gene regulation, and in particular from the substantial induction of IκBα, but not IκBβ, gene expression post-NF-κB activation. In the present study, we probe the differential effects of IL (interleukin)-1β on induction of IκBα and perform the first characterization of the human IκBβ promoter. A consensus NF-κB-binding site, capable of binding NF-κB both in vitro and in vivo, is found in the IκBβ gene 5′ flanking region. However, the IκBβ promoter was not substantially activated by pro-inflammatory cytokines, such as IL-1β and tumour necrosis factor α, that are known to cause strong activation of NF-κB. Furthermore, in contrast with IκBα, NF-κB activation did not increase expression of endogenous IκBβ as assessed by analysis of mRNA and protein levels. Unlike κB-responsive promoters, IκBβ promoter-bound p65 inefficiently recruits RNA polymerase II, which stalls at the promoter. We present evidence that this stalling is likely due to the absence of transcription factor IIH engagement, a prerequisite for RNA polymerase II phosphorylation and transcriptional initiation. Differences in the conformation of promoter-bound NF-κB may underlie the variation in the ability to engage the basal transcriptional apparatus at the IκBβ and κB-responsive promoters. This accounts for the differential expression of IκB family members in response to NF-κB activation and furthers our understanding of the mechanisms involved in transcription factor activity and IκBβ gene regulation.

A region internal to the coding sequences is essential for transcription of the yeast Ty-D15 element

1989 ◽  
Vol 9 (9) ◽  
pp. 3667-3678
Author(s):  
K Yu ◽  
R T Elder
Keyword(s):  
Rna Polymerase ◽  
Transposable Element ◽  
Rna Polymerase Ii ◽  
Initiation Site ◽  
Direct Repeats ◽  
Yeast Gene ◽  
Base Pairs ◽  
Transcriptional Initiation ◽  
Coding Sequences ◽  
Transcription Signals

The major transcript of the yeast transposable element Ty1 has its 5' end in one delta and the 3' end in the opposite delta, the direct repeats of about 335 base pairs (bp) at each end of the element. The transcriptional initiation signals of the Ty-D15 element that give rise to this transcript were found to have a number of unusual characteristics. The 5' delta by itself, which contained the initiation site for Ty transcription, gave no detectable transcription. A region internal to the transcript in a translated part of the element and about 140 bp downstream of the 5' delta was essential for initiation of the major Ty transcript. This internal activating region (IAR) had several interesting properties. When the portion of the delta upstream of the initiation site was replaced with DNA fragments that did not by themselves act as promoters, initiation directed by the IAR still occurred at about the same position, 200 to 400 bp upstream of the IAR. If fragments containing the IAR were inverted, transcription could still occur. When 468 or 636 bp was inserted between the delta and the IAR, initiations occurred near the normal delta initiation site and in the inserted DNA. Therefore, the location and properties of transcription signals for Ty-D15 differ considerably from those expected for a yeast gene transcribed by RNA polymerase II.

scholarly journals Heat Shock Causes a Reversible Increase in RNA Polymerase II Occupancy Downstream of mRNA Genes, Consistent with a Global Loss in Transcriptional Termination

2018 ◽  
Vol 38 (18) ◽  
Author(s):  
Joseph F. Cardiello ◽  
James A. Goodrich ◽  
Jennifer F. Kugel
Keyword(s):  
Heat Shock ◽  
Rna Polymerase ◽  
Rna Polymerase Ii ◽  
Transcriptional Repression ◽  
Normal Growth ◽  
Global Changes ◽  
Transcriptional Initiation ◽  
Pol Ii ◽  
Transcriptional Termination ◽  
Number Of Genes

ABSTRACT Cellular transcriptional programs are tightly controlled but can profoundly change in response to environmental challenges or stress. Here we describe global changes in mammalian RNA polymerase II (Pol II) occupancy at mRNA genes in response to heat shock and after recovery from the stress. After a short heat shock, Pol II occupancy across thousands of genes decreased, consistent with widespread transcriptional repression, whereas Pol II occupancy increased at a small number of genes in a manner consistent with activation. Most striking, however, was loss of the Pol II peak near the 3′ ends of mRNA genes, coupled to a gain in polymerase occupancy extending tens of kilobases downstream of 3′ ends. Typical patterns of 3′ end occupancy were largely restored 60 min after cells returned to normal growth temperatures. These changes in polymerase occupancy revealed a heat shock-induced loss of normal termination, which was potent, global, and reversible. The occupancy of the termination factor CPSF73 at the 3′ ends of representative genes was reduced after heat shock, suggesting a mechanism for impaired termination. The data support a model in which heat shock induces widespread repression of transcriptional initiation and loss of transcription termination, which reverses as cells return to homeostasis.

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