scholarly journals The Saccharomyces cerevisiae SPT7 gene encodes a very acidic protein important for transcription in vivo.

Genetics ◽  
1995 ◽  
Vol 139 (2) ◽  
pp. 523-536 ◽  
Author(s):  
L J Gansheroff ◽  
C Dollard ◽  
P Tan ◽  
F Winston

Abstract Mutations in the SPT7 gene of Saccharomyces cerevisiae originally were identified as suppressors of Ty and delta insertion mutations in the 5' regions of the HIS4 and LYS2 genes. Other genes that have been identified in mutant hunts of this type have been shown to play a role in transcription. In this work we show that SPT7 is also important for proper transcription in vivo. We have cloned and sequenced the SPT7 gene and have shown that it encodes a large, acidic protein that is localized to the nucleus. The SPT7 protein contains a bromodomain sequence; a deletion that removes the bromodomain from the SPT7 protein causes no detectable mutant phenotype. Strains that contain an spt7 null mutation are viable but grow very slowly and have transcriptional defects at many loci including insertion mutations, Ty elements, the INO1 gene and the MFA1 gene. These transcriptional defects and other mutant phenotypes are similar to those caused by certain mutations in SPT15, which encodes the TATA binding protein (TBP). The similarity of the phenotypes of spt7 and spt15 mutants, including effects of spt7 mutations on the transcription start site of certain genes, suggests that SPT7 plays an important role in transcription initiation in vivo.

2016 ◽  
Vol 113 (21) ◽  
pp. E2899-E2905 ◽  
Author(s):  
Irina O. Vvedenskaya ◽  
Hanif Vahedian-Movahed ◽  
Yuanchao Zhang ◽  
Deanne M. Taylor ◽  
Richard H. Ebright ◽  
...  

During transcription initiation, RNA polymerase (RNAP) holoenzyme unwinds ∼13 bp of promoter DNA, forming an RNAP-promoter open complex (RPo) containing a single-stranded transcription bubble, and selects a template-strand nucleotide to serve as the transcription start site (TSS). In RPo, RNAP core enzyme makes sequence-specific protein–DNA interactions with the downstream part of the nontemplate strand of the transcription bubble (“core recognition element,” CRE). Here, we investigated whether sequence-specific RNAP–CRE interactions affect TSS selection. To do this, we used two next-generation sequencing-based approaches to compare the TSS profile of WT RNAP to that of an RNAP derivative defective in sequence-specific RNAP–CRE interactions. First, using massively systematic transcript end readout, MASTER, we assessed effects of RNAP–CRE interactions on TSS selection in vitro and in vivo for a library of 47 (∼16,000) consensus promoters containing different TSS region sequences, and we observed that the TSS profile of the RNAP derivative defective in RNAP–CRE interactions differed from that of WT RNAP, in a manner that correlated with the presence of consensus CRE sequences in the TSS region. Second, using 5′ merodiploid native-elongating-transcript sequencing, 5′ mNET-seq, we assessed effects of RNAP–CRE interactions at natural promoters in Escherichia coli, and we identified 39 promoters at which RNAP–CRE interactions determine TSS selection. Our findings establish RNAP–CRE interactions are a functional determinant of TSS selection. We propose that RNAP–CRE interactions modulate the position of the downstream end of the transcription bubble in RPo, and thereby modulate TSS selection, which involves transcription bubble expansion or transcription bubble contraction (scrunching or antiscrunching).


1996 ◽  
Vol 16 (6) ◽  
pp. 3206-3213 ◽  
Author(s):  
S M Roberts ◽  
F Winston

Mutations selected as suppressors of Ty and solo delta insertion mutations is Saccharomyces cerevisiae have identified a number of genes important for transcription initiation. One of these gens, SPT15, encodes the TATA-binding protein, and three others, SPT3, SPT7, and SPT8, encode proteins functionally related to the TATA-binding protein. To identify additional related functions, we have selected for new spt mutations. This work has identified one new gene, SPT20. Null mutations in SPT20 cause poor growth and a set of severe transcriptional defects very similar to those caused by null mutations in SPT3, SPT7, and SPT8 and also very similar to those caused by certain missense mutations in SPT15. Consistent with its having an important function in transcription in vivo, SPT20 was also recently identified as ADA5 and has been shown to be important for transcriptional activation (G.A. Marcus, J. Horiuchi, N. Silverman, and L. Guarente, Mol. Cell. Biol. 16:3197-3205, 1996.


1996 ◽  
Vol 16 (11) ◽  
pp. 6436-6443 ◽  
Author(s):  
C W Lin ◽  
B Moorefield ◽  
J Payne ◽  
P Aprikian ◽  
K Mitomo ◽  
...  

We report the cloning of RRN11, a gene coding for a 66-kDa protein essential for transcription initiation by RNA polymerase I (Pol I) in the yeast Saccharomyces cerevisiae. Rrn11 specifically complexes with two previously identified transcription factors, Rrn6 and Rrn7 (D. A. Keys, J. S. Steffan, J. A. Dodd, R. T. Yamamoto, Y. Nogi, and M. Nomura, Genes Dev. 8:2349-2362, 1994). The Rrn11-Rrn6-Rrn7 complex also binds the TATA-binding protein and is required for transcription by the core domain of the Pol I promoter. Therefore, we have designated the Rrn11-Rrn6-Rrn7-TATA-binding protein complex the yeast Pol I core factor. A two-hybrid assay was used to demonstrate involvement of short leucine heptad repeats on both Rrn11 and Rrn6 in the in vivo association of these two proteins. This assay also verified the previously described strong association between Rrn6 and Rrn7, independent of the Rrn6 leucine repeat.


2018 ◽  
Author(s):  
Christoph S. Börlin ◽  
Nevena Cvetesic ◽  
Petter Holland ◽  
David Bergenholm ◽  
Verena Siewers ◽  
...  

ABSTRACTOne of the fundamental processes that determine cellular fate is regulation of gene transcription. Understanding these regulatory processes is therefore essential for understanding cellular responses to changes in environmental conditions. At the core promoter, the regulatory region containing the transcription start site (TSS), all inputs regulating transcription are integrated. Here, we used Cap Analysis of Gene Expression (CAGE) to analyze the pattern of transcription start sites at four different environmental conditions (limited in ethanol, limited in nitrogen, limited in glucose and limited in glucose under anaerobic conditions) using the Saccharomyces cerevisiae strain CEN.PK113-7D. With this experimental setup we were able to show that the TSS landscape in yeast is stable at different metabolic states of the cell. We also show that the shape index, a characteristic feature of each TSS describing the spatial distribution of transcription initiation events, has a surprisingly strong negative correlation with the measured expression levels. Our analysis supplies a set of high quality TSS annotations useful for metabolic engineering and synthetic biology approaches in the industrially relevant laboratory strain CEN.PK113-7D, and provides novel insights into yeast TSS dynamics and gene regulation.


eLife ◽  
2017 ◽  
Vol 6 ◽  
Author(s):  
Libing Yu ◽  
Jared T Winkelman ◽  
Chirangini Pukhrambam ◽  
Terence R Strick ◽  
Bryce E Nickels ◽  
...  

During transcription initiation, RNA polymerase (RNAP) binds to promoter DNA, unwinds promoter DNA to form an RNAP-promoter open complex (RPo) containing a single-stranded ‘transcription bubble,’ and selects a transcription start site (TSS). TSS selection occurs at different positions within the promoter region, depending on promoter sequence and initiating-substrate concentration. Variability in TSS selection has been proposed to involve DNA ‘scrunching’ and ‘anti-scrunching,’ the hallmarks of which are: (i) forward and reverse movement of the RNAP leading edge, but not trailing edge, relative to DNA, and (ii) expansion and contraction of the transcription bubble. Here, using in vitro and in vivo protein-DNA photocrosslinking and single-molecule nanomanipulation, we show bacterial TSS selection exhibits both hallmarks of scrunching and anti-scrunching, and we define energetics of scrunching and anti-scrunching. The results establish the mechanism of TSS selection by bacterial RNAP and suggest a general mechanism for TSS selection by bacterial, archaeal, and eukaryotic RNAP.


2017 ◽  
Author(s):  
Libing Yu ◽  
Jared T. Winkelman ◽  
Chirangini Pukhrambam ◽  
Terence R. Strick ◽  
Bryce E. Nickels ◽  
...  

SUMMARYDuring transcription initiation, RNA polymerase (RNAP) binds to promoter DNA, unwinds promoter DNA to form an RNAP-promoter open complex (RPo) containing a single-stranded "transcription bubble," and selects a transcription start site (TSS). TSS selection occurs at different positions within the promoter region, depending on promoter sequence and initiating-substrate concentration. Variability in TSS selection has been proposed to involve DNA "scrunching" and "antiscrunching," the hallmarks of which are: (i) forward and reverse movement of the RNAP leading edge, but not trailing edge, relative to DNA, and (ii) expansion and contraction of the transcription bubble. Here, using in vitro and in vivo protein-DNA photocrosslinking and single-molecule nanomanipulation, we show bacterial TSS selection exhibits both hallmarks of scrunching and anti-scrunching, and we define energetics of scrunching and anti-scrunching. The results establish the mechanism of TSS selection by bacterial RNAP and suggest a general mechanism for TSS selection by bacterial, archaeal, and eukaryotic RNAP.


2021 ◽  
Author(s):  
Yunye Zhu ◽  
Irina O. Vvedenskaya ◽  
Bryce E. Nickels ◽  
Craig D. Kaplan

DNA sequence at Transcription Start Sites (TSSs) is a key determinant of initiation by RNA Polymerase II (Pol II). To function as a TSS, an initiation compatible sequence must be specified by a promoter in an appropriate chromatin context. We report the development of a method for quantitative analysis of transcription initiation by Pol II that involves construction of DNA libraries of barcoded promoter variants, production of RNA transcripts, and analysis of transcript 5' ends and transcript yields (Pol II MAssively Systematic Transcript End Readout, "Pol II MASTER"). Using Pol II MASTER, we measure the efficiency of transcription initiation during promoter scanning by Saccharomyces cerevisiae Pol II for ~1 million unique TSS sequences. Furthermore, we employ Pol II MASTER to determine how Pol II activity, known to widely alter TSS selection in vivo, alters TSS efficiencies across our promoter variants. Pol II MASTER recapitulates known critical qualities of Saccharomyces cerevisiae TSS -8, -1, and +1 positions while demonstrating that surrounding sequences modulate initiation efficiency over a wide range. We discover functional interactions between neighboring sequence positions, indicating that adjacent positions likely function together. We demonstrate that initiation efficiencies are altered for +1 A TSSs relative to +1 G TSSs when Pol II activity is perturbed through genetic means. Pol II MASTER provides data for predictive models of TSS initiation efficiency at genomic promoters.


1990 ◽  
Vol 10 (6) ◽  
pp. 2832-2839
Author(s):  
A S Ponticelli ◽  
K Struhl

The promoter region of the Saccharomyces cerevisiae his3 gene contains two TATA elements, TC and TR, that direct transcription initiation to two sites designated +1 and +13. On the basis of differences between their nucleotide sequences and their responsiveness to upstream promoter elements, it has previously been proposed that TC and TR promote transcription by different molecular mechanisms. To begin a study of his3 transcription in vitro, we used S. cerevisiae nuclear extracts together with various DNA templates and transcriptional activator proteins that have been characterized in vivo. We demonstrated accurate transcription initiation in vitro at the sites used in vivo, transcriptional activation by GCN4, and activation by a GAL4 derivative on various gal-his3 hybrid promoters. In all cases, transcription stimulation was dependent on the presence of an acidic activation region in the activator protein. In addition, analysis of promoters containing a variety of TR derivatives indicated that the level of transcription in vitro was directly related to the level achieved in vivo. The results demonstrated that the in vitro system accurately reproduced all known aspects of in vivo his3 transcription that depend on the TR element. However, in striking contrast to his3 transcription in vivo, transcription in vitro yielded approximately 20 times more of the +13 transcript than the +1 transcript. This result was not due to inability of the +1 initiation site to be efficiently utilized in vitro, but rather it reflects the lack of TC function in vitro. The results support the idea that TC and TR mediate transcription from the wild-type promoter by distinct mechanisms.


1993 ◽  
Vol 13 (7) ◽  
pp. 3841-3849
Author(s):  
B Zenzie-Gregory ◽  
A Khachi ◽  
I P Garraway ◽  
S T Smale

Promoters containing Sp1 binding sites and an initiator element but lacking a TATA box direct high levels of accurate transcription initiation by using a mechanism that requires the TATA-binding protein (TBP). We have begun to address the role of TBP during transcription from Sp1-initiator promoters by varying the nucleotide sequence between -14 and -33 relative to the start site. With each of several promoters containing different upstream sequences, we detected accurate transcription both in vitro and in vivo, but the promoter strengths varied widely, particularly with the in vitro assay. The variable promoter activities correlated with, but were not proportional to, the abilities of the upstream sequences to function as TATA boxes, as assessed by multiple criteria. These results confirm that accurate transcription can proceed in the presence of an initiator, regardless of the sequence present in the -30 region. However, the results reveal a role for this upstream region, most consistent with a model in which initiator-mediated transcription requires binding of TBP to the upstream DNA in the absence of a specific recognition sequence. Moreover, in vivo it appears that the promoter strength is modulated less severely by altering the -30 sequence, consistent with a previous suggestion that TBP is not rate limiting in vivo for TATA-less promoters. Taken together, these results suggest that variations in the structure of a core promoter might alter the rate-limiting step for transcription initiation and thereby alter the potential modes of transcriptional regulation, without severely changing the pathway used to assemble a functional preinitiation complex.


1994 ◽  
Vol 14 (1) ◽  
pp. 189-199
Author(s):  
D S Pederson ◽  
T Fidrych

After each round of replication, new transcription initiation complexes must assemble on promoter DNA. This process may compete with packaging of the same promoter sequences into nucleosomes. To elucidate interactions between regulatory transcription factors and nucleosomes on newly replicated DNA, we asked whether heat shock factor (HSF) could be made to bind to nucleosomal DNA in vivo. A heat shock element (HSE) was embedded at either of two different sites within a DNA segment that directs the formation of a stable, positioned nucleosome. The resulting DNA segments were coupled to a reporter gene and transfected into the yeast Saccharomyces cerevisiae. Transcription from these two plasmid constructions after induction by heat shock was similar in amount to that from a control plasmid in which HSF binds to nucleosome-free DNA. High-resolution genomic footprint mapping of DNase I and micrococcal nuclease cleavage sites indicated that the HSE in these two plasmids was, nevertheless, packaged in a nucleosome. The inclusion of HSE sequences within (but relatively close to the edge of) the nucleosome did not alter the position of the nucleosome which formed with the parental DNA fragment. Genomic footprint analyses also suggested that the HSE-containing nucleosome was unchanged by the induction of transcription. Quantitative comparisons with control plasmids ruled out the possibility that HSF was bound only to a small fraction of molecules that might have escaped nucleosome assembly. Analysis of the helical orientation of HSE DNA in the nucleosome indicated that HSF contacted DNA residues that faced outward from the histone octamer. We discuss the significance of these results with regard to the role of nucleosomes in inhibiting transcription and the normal occurrence of nucleosome-free regions in promoters.


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