Promoter DNA sequence guides factors that position the +1 nucleosome and facilitate TBP binding
Ontology highlight
ABSTRACT:
ORGANISM(S): Saccharomyces cerevisiae W303 Saccharomyces cerevisiae S288C Saccharomyces cerevisiae
PROVIDER: GSE98260 | GEO | 2018/06/01
REPOSITORIES: GEO
Similar Datasets
Project description:Here we present evidence that precise positioning of the +1 promoter nucleosome in yeast is critical for efficient TBP binding and pre-initiation complex assembly, and is determined, at least in part, by the action of two key factors, the essential chromatin remodeler RSC and one (or more) of a small set of ubiquitous pioneer transcription factors (PTFs). Despite their widespread co-localization, we show that RSC and PTFs often act independently to generate accessible chromatin. Furthermore, we present evidence that RSC binding, as well as the strength and directionality of its action on nucleosomes, depends upon the arrangement of two specific DNA motifs relative to nearby PTF binding sites. Our results provide insights into how promoter DNA sequence instructs trans-acting factors to precisely control nucleosome architecture and stimulate transcription initiation.
2018-06-01 | GSE98259 | GEO
Project description:Here we present evidence that precise positioning of the +1 promoter nucleosome in yeast is critical for efficient TBP binding and pre-initiation complex assembly, and is determined, at least in part, by the action of two key factors, the essential chromatin remodeler RSC and one (or more) of a small set of ubiquitous pioneer transcription factors (PTFs). Despite their widespread co-localization, we show that RSC and PTFs often act independently to generate accessible chromatin. Furthermore, we present evidence that RSC binding, as well as the strength and directionality of its action on nucleosomes, depends upon the arrangement of two specific DNA motifs relative to nearby PTF binding sites. Our results provide insights into how promoter DNA sequence instructs trans-acting factors to precisely control nucleosome architecture and stimulate transcription initiation.
2018-06-01 | GSE98205 | GEO
Project description:Promoter DNA sequence guides factors that position the +1 nucleosome and facilitate TBP binding
| PRJNA384436 | ENA
Project description:Promoter DNA sequence guides factors that position the +1 nucleosome and facilitate TBP binding [array]
| PRJNA384442 | ENA
Project description:Nucleosome assembly during DNA replication is tightly coupled to ongoing DNA synthesis. This process, termed DNA replication-coupled (RC) nucleosome assembly, is essential for chromatin replication and has a great impact on both genome stability maintenance and epigenetic inheritance. This review discusses a set of recent findings regarding the role of replisome components contributing to RC nucleosome assembly. Starting with a brief introduction to the factors involved in nucleosome assembly and some aspects of the architecture of the eukaryotic replisome, we discuss studies from yeast to mammalian cells and the interactions of replisome components with histones and histone chaperones. We describe the proposed functions of replisome components during RC nucleosome assembly and discuss their impacts on histone segregation and implications for epigenetic inheritance.
| S-EPMC7066812 | biostudies-literature
Project description:Nucleosome-depleted regions (NDRs) are ubiquitous on eukaryotic promoters. The formation of many NDRs cannot be readily explained by previously proposed mechanisms. Here, we carry out a focused study on a physiologically important NDR in the yeast CLN2 promoter (CLN2pr). We show that this NDR does not result from intrinsically unfavorable histone-DNA interaction. Instead, we identified eight conserved factor binding sites, including that of Reb1, Mcm1, and Rsc3, that cause the local nucleosome depletion. These nucleosome-depleting factors (NDFs) work redundantly, and simultaneously mutating all their binding sites eliminates CLN2pr NDR. The loss of the NDR induces unreliable "on/off" expression in individual cell cycles, but in the presence of the NDR, NDFs have little direct effect on transcription. We present bioinformatic evidence that the formation of many NDRs across the genome involves multiple NDFs. Our findings also provide significant insight into the composition and spatial organization of functional promoters.
| S-EPMC3119483 | biostudies-literature
Project description:The TATA-box binding protein (TBP) is required by eukaryotic RNA polymerases to bind to the TATA box, an eight-basepair DNA promoter element, to initiate transcription. Carcinogen adducts that bind to the TATA box can hamper this important process. Benzo[a]pyrene (BP) is a representative chemical carcinogen that can be metabolically converted to highly reactive benzo[a]pyrene diol epoxides (BPDE), which in turn can form chemically stereoisomeric BP-DNA adducts. Depending on the TATA-bound adduct's location and stereochemistry, TATA/TBP binding can be decreased or increased. Our previous study interpreted the location-dependent effect in terms of conformational freedom and major-groove space available to BP. Here we further explore specific structural changes of the TATA/TBP complex to help interpret the stereochemical effect in terms of the flexibility of the TATA bases that frame the intercalated adduct. Thermodynamic analyses using molecular mechanics Poisson-Boltzmann surface area (MM-PBSA) yield large standard deviations, which make the computed binding free energies the same within the error bars and point to current limitations of free energy calculations of large and highly charged systems like DNA/protein complexes.
| S-EPMC1386768 | biostudies-literature
Project description:BackgroundTrypanosomatid genomes are colonized by active and inactive mobile DNA elements, such as LINE, SINE-like, SIDER and DIRE retrotransposons. These elements all share a 77-nucleotide-long sequence at their 5' ends, known as Pr77, which activates transcription, thereby generating abundant unspliced and translatable transcripts. However, transcription factors that mediates this process have still not been reported.MethodsTATA-binding protein (TBP) and small nuclear RNA-activating protein 50 kDa (SNAP50) recombinant proteins and specific antibodies raised against them were generated. Protein capture assay, electrophoretic mobility-shift assays (EMSA) and EMSA competition assays carried out using these proteins and nuclear proteins of the parasite together to specific DNA sequences used as probes allowed detecting direct interaction of these transcription factors to Pr77 sequence.ResultsThis study identified TBP and SNAP50 as part of the DNA-protein complex formed by the Pr77 promoter sequence and nuclear proteins of Trypanosoma cruzi. TBP establishes direct and specific contact with the Pr77 sequence, where the DPE and DPE downstream regions are docking sites with preferential binding. TBP binds cooperatively (Hill coefficient = 1.67) to Pr77 and to both strands of the Pr77 sequence, while the conformation of this highly structured sequence is not involved in TBP binding. Direct binding of SNAP50 to the Pr77 sequence is weak and may be mediated by protein-protein interactions through other trypanosomatid nuclear proteins.ConclusionsIdentification of the transcription factors that mediate Pr77 transcription may help to elucidate how these retrotransposons are mobilized within the trypanosomatid genomes and their roles in gene regulation processes in this human parasite.
| S-EPMC8190864 | biostudies-literature
Project description:The TATA box-binding protein (TBP) is highly conserved throughout eukaryotes and plays a central role in the assembly of the transcription preinitiation complex (PIC) at gene promoters. TBP binds and bends DNA, and directs adjacent binding of the transcription factors TFIIA and TFIIB for PIC assembly. Here, we show that yeast TBP can bind to a nucleosome containing the Widom-601 sequence and that TBP-nucleosome binding is stabilized by TFIIA. We determine three cryo-electron microscopy (cryo-EM) structures of TBP-nucleosome complexes, two of them containing also TFIIA. TBP can bind to superhelical location (SHL) -6, which contains a TATA-like sequence, but also to SHL +2, which is GC-rich. Whereas binding to SHL -6 can occur in the absence of TFIIA, binding to SHL +2 is only observed in the presence of TFIIA and goes along with detachment of upstream terminal DNA from the histone octamer. TBP-nucleosome complexes are sterically incompatible with PIC assembly, explaining why a promoter nucleosome generally impairs transcription and must be moved before initiation can occur.
| S-EPMC8325331 | biostudies-literature
Project description:The TATA binding protein (TBP) is a critical transcription factor used for nucleating assembly of the RNA polymerase II machinery. TBP binds TATA box elements with high affinity and kinetic stability and in vivo is correlated with high levels of transcription activation. However, since most promoters use less stable TATA-less or TATA-like elements, while also competing with nucleosome occupancy, further mechanistic insight into TBP's DNA binding properties and ability to access chromatin is needed. Using bulk and single-molecule FRET, we find that TBP binds a minimal consensus TATA box as a two-state equilibrium process, showing no evidence for intermediate states. However, upon addition of flanking DNA sequence, we observe non-specific cooperative binding to multiple DNA sites that compete for TATA-box specificity. Thus, we conclude that TBP binding is defined by a branched pathway, wherein TBP initially binds with little sequence specificity and is thermodynamically positioned by its kinetic stability to the TATA box. Furthermore, we observed the real-time access of TBP binding to TATA box DNA located within the DNA entry-exit site of the nucleosome. From these data, we determined salt-dependent changes in the nucleosome conformation regulate TBP's access to the TATA box, where access is highly constrained under physiological conditions, but is alleviated by histone acetylation and TFIIA.
| S-EPMC4081063 | biostudies-literature