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Query: UNIPROT:P20226 (
TATA-binding protein
)
1,297
document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)
BINDING of the
TATA-binding protein
(
TBP
) to the TATA box is required for transcription from many eukaryotic promoters in gene expression. Regulation of this binding is therefore likely to be an important determinant of promoter activity. Incorporation of the TATA sequence into nucleosomes dramatically reduces transcription initiation, presumably because of stereochemical constraints on binding of general transcription factors. Biochemical and genetic studies imply that cellular factors such as yeast SWI/SNF are required for activator function and might alter chromatin structure. One step that could be regulated during the activation process is
TBP
binding in chromatin 12, 13. We show here that binding of
TBP
to the TATA sequence is severely inhibited by incorporation of this sequence into a nucleosome. Inhibition can be overcome by ATP-dependent alterations in nucleosomal DNA structure mediated by hSWI/SNF, a putative human homologue of the yeast SWI/SNF complex. Additionally, the orientation of the TATA sequence relative to the surface of the
histone
core affects the access of
TBP
. We propose that the dynamic remodelling of chromatin structure to allow
TBP
binding is a key step in the regulation of eukaryotic gene expression.
...
PMID:Facilitated binding of TATA-binding protein to nucleosomal DNA. 804 59
In eukaryotic cells the
TATA-binding protein
(
TBP
) associates with other proteins known as
TBP
-associated factors (TAFs) to form multisubunit transcription factors important for gene expression by all three nuclear RNA polymerases. Computer searching of the complete Saccharomyces cerevisiae genome revealed five previously unidentified yeast genes with significant sequence similarity to known human and Drosophila RNA polymerase II TAFs. Each of these genes is essential for viability. A sixth essential gene (FUN81) has previously been noted to be similar to human TAFII18. Coimmunoprecipitation experiments show that all six proteins are associated with
TBP
, demonstrating that they are true TAFs. Furthermore, these proteins are present in complexes containing the TAFII130 subunit, indicating that they are components of TFIID. Based on their predicted molecular weights, these genes have been designated TAF67, TAF61(68), TAF40, TAF23(25), TAF19(FUN81), and TAF17. Yeast TAF61 is significantly larger than its higher eukaryotic homologues, and deletion analysis demonstrates that the evolutionarily conserved,
histone
-like domain is sufficient and necessary to support viability.
...
PMID:Yeast homologues of higher eukaryotic TFIID subunits. 896 9
Human transcription initiation factor TFIID contains the
TATA-binding protein
(
TBP
) and several
TBP
-associated factors (TAFs). To investigate the structural organization and function of TFIID, we have cloned and expressed a DNA encoding the third largest human TFIID subunit, hTAFII100. Immunoprecipitation studies demonstrate that hTAFII100 is an integral subunit that is associated with all transcriptionally-competent forms of TFIID. They further suggest that at least part of the N-terminal region lies on the surface of TFIID, while a C-terminal region containing conserved WD-40 repeats appears inaccessible. Both in vivo and in vitro assays indicate that hTAFII100 interacts strongly with the histone H4-related hTAFII80 and the histone H3-related hTAFII31, as well as a stable complex comprised of both hTAFII80 and hTAFII31. Apparently weaker interactions of hTAFII100 with
TBP
, hTAFII250, hTAFII28, and hTAFII20, but not hTAFII55, also have been observed. These results suggest a role for hTAFII100 in stabilizing interactions of TAFs, especially the
histone
-like TAFs, in TFIID. In addition, functional studies show that anti-hTAFII100 antibodies selectively inhibit basal transcription from a TATA-less initiator-containing promoter, relative to a TATA-containing promoter, suggesting a possible core promoter-specific function for hTAFII100.
...
PMID:Specific interactions and potential functions of human TAFII100. 904 4
The transcriptional adaptor protein Gcn5 has been identified as a nuclear histone acetyltransferase (HAT). Although recombinant yeast Gcn5 efficiently acetylates free histones, it fails to acetylate histones contained in nucleosomes, indicating that additional components are required for acetylation of chromosomal histones. We report here that Gcn5 functions as a catalytic subunit in two high-molecular-mass native HAT complexes, with apparent molecular masses of 0.8 and 1.8 megadalton (MD), respectively, which acetylate nucleosomal histones. Both the 0.8- and 1.8-MD Gcn5-containing complexes cofractionate with Ada2 and are lost in gcn5delta, ada2delta, or ada3delta yeast strains, illustrating that these HAT complexes are bona fide native Ada-transcriptional adaptor complexes. Importantly, the 1.8-MD adaptor/HAT complex also contains Spt gene products that are linked to
TATA-binding protein
(
TBP
) function. This complex is lost in spt20/ada5delta and spt7delta strains and Spt3, Spt7, Spt20/Ada5, Ada2, and Gcn5 all copurify with this nucleosomal HAT complex. Therefore, the 1.8-MD adaptor/HAT complex illustrates an interaction between Ada and Spt gene products and confirms the existence of a complex containing the
TBP
group of Spt proteins as demonstrated by genetic and biochemical studies. We have named this novel transcription regulatory complex SAGA (Spt-Ada-Gcn5-Acetyltransferase). The function of Gcn5 as a histone acetyltransferase within the Ada and SAGA adaptor complexes indicates the importance of
histone
acetylation during steps in transcription activation mediated by interactions with transcription activators and general transcription factors (i.e.,
TBP
).
...
PMID:Yeast Gcn5 functions in two multisubunit complexes to acetylate nucleosomal histones: characterization of an Ada complex and the SAGA (Spt/Ada) complex. 922 14
Sin mutations in Saccharomyces cerevisiae alleviate transcriptional defects that result from the inactivation of the yeast SWVI/SNF complex. We have investigated the structural and functional consequences for the nucleosome of Sin mutations in histone H3. We directly test the hypothesis that mutations in histone H3 leading to a SWI/SNF-independent (Sin) phenotype in yeast lead to nucleosomal destabilization. In certain instances this is shown to be true; however, nucleosomal destabilization does not always occur. Topoisomerase I-mediated relaxation of minichromosomes assembled with either mutant histone H3 or wild-type H3 together with histones H2A, H2B, and H4 indicates that DNA is constrained into nucleosomal structures containing either mutant or wild-type proteins. However, nucleosomes containing particular mutant H3 molecules (R116-H and T118-I) are more accessible to digestion by micrococcal nuclease and do not constrain DNA in a precise rotational position, as revealed by digestion with DNase I. This result establishes that Sin mutations in histone H3 located close to the dyad axis can destabilize
histone
-DNA contacts at the periphery of the nucleosome core. Other nucleosomes containing a distinct mutant H3 molecule (E105-K) associated with a Sin phenotype show very little change in nucleosome structure and stability compared to wild-type nucleosomes. Both mutant and wild-type nucleosomes continue to restrict the binding of either
TATA-binding protein
/transcription factor IIA (TFIIA) or the RNA polymerase III transcription machinery. Thus, different Sin mutations in histone H3 alter the stability of
histone
-DNA interactions to various extents in the nucleosome while maintaining the fundamental architecture of the nucleosome and contributing to a common Sin phenotype.
...
PMID:Sin mutations of histone H3: influence on nucleosome core structure and function. 937 28
SAGA, a recently described protein complex in Saccharomyces cerevisiae, is important for transcription in vivo and possesses
histone
acetylation function. Here we report both biochemical and genetic analyses of members of three classes of transcription regulatory factors contained within the SAGA complex. We demonstrate a correlation between the phenotypic severity of SAGA mutants and SAGA structural integrity. Specifically, null mutations in the Gcn5/Ada2/Ada3 or Spt3/Spt8 classes cause moderate phenotypes and subtle structural alterations, while mutations in a third subgroup, Spt7/Spt20, as well as Ada1, disrupt the complex and cause severe phenotypes. Interestingly, double mutants (gcn5Delta spt3Delta and gcn5Delta spt8Delta) causing loss of a member of each of the moderate classes have severe phenotypes, similar to spt7Delta, spt20Delta, or ada1Delta mutants. In addition, we have investigated biochemical functions suggested by the moderate phenotypic classes and find that first, normal nucleosomal acetylation by SAGA requires a specific domain of Gcn5, termed the bromodomain. Deletion of this domain also causes specific transcriptional defects at the HIS3 promoter in vivo. Second, SAGA interacts with TBP, the
TATA-binding protein
, and this interaction requires Spt8 in vitro. Overall, our data demonstrate that SAGA harbors multiple, distinct transcription-related functions, including direct TBP interaction and nucleosomal
histone
acetylation. Loss of either of these causes slight impairment in vivo, but loss of both is highly detrimental to growth and transcription.
...
PMID:Functional organization of the yeast SAGA complex: distinct components involved in structural integrity, nucleosome acetylation, and TATA-binding protein interaction. 985 34
Coexpression of the human
TATA-binding protein
(
TBP
)-associated factor 28 (hTAFII28) with the altered-specificity mutant
TBP
spm3 synergistically enhances transcriptional activation by the activation function 2 of the nuclear receptors (NRs) for estrogen and vitamin D3 from a reporter plasmid containing a TGTA element in mammalian cells. This synergy is abolished by mutation of specific amino acids in the alpha2-helix of the
histone
fold in the conserved C-terminal region of hTAFII28. Critical amino acids are found on both the exposed hydrophilic face of this helix and the hydrophobic interface with TAFII18. This alpha-helix of hTAFII28 therefore mediates multiple interactions required for coactivator activity. We further show that mutation of specific residues in the H1' alpha-helix of
TBP
either reduces or increases interactions with hTAFII28. The mutations which reduce interactions with hTAFII28 do not affect functional synergy, whereas the
TBP
mutation which increases interaction with hTAFII28 is defective in its ability to synergistically enhance activation by NRs. However, this
TBP
mutant supports activation by other activators and is thus specifically defective for its ability to synergize with hTAFII28.
...
PMID:Synergistic transcriptional activation by TATA-binding protein and hTAFII28 requires specific amino acids of the hTAFII28 histone fold. 1037 54
RNA polymerase (RNAP) purified from Methanobacterium thermoautotrophicum DeltaH has been shown to initiate transcription accurately in vitro from the hmtB archaeal
histone
promoter with either native or recombinant forms of the M. thermoautotrophicum
TATA-binding protein
and transcription factor TFB. Efforts to obtain transcription initiation from hydrogen-regulated methane gene promoters were, however, unsuccessful. Two previously unrecognized archaeal RNAP subunits have been identified, and complex formation by the M. thermoautotrophicum RNAP and TFB has been demonstrated.
...
PMID:Methanobacterium thermoautotrophicum RNA polymerase and transcription in vitro. 1040 Jun 4
The RNA polymerase II general transcription factor TFIID is a complex containing the
TATA-binding protein
(
TBP
) and associated factors (TAFs). We have used a mutant allele of the gene encoding yeast TAF(II)68/61p to analyze its function in vivo. We provide biochemical and genetic evidence that the C-terminal alpha-helix of TAF(II)68/61p is required for its direct interaction with
TBP
, the stable incorporation of
TBP
into the TFIID complex, the integrity of the TFIID complex, and the transcription of most genes in vivo. This is the first evidence that a yeast TAF(II) other than TAF(II)145/130 interacts with
TBP
, and the implications of this on the interpretation of data obtained studying TAF(II) mutants in vivo are discussed. We have identified a high copy suppressor of the TAF68/61 mutation, TSG2, that has sequence similarity to a region of the SAGA subunit Ada1. We demonstrate that it directly interacts with TAF(II)68/61p in vitro, is a component of TFIID, is required for the stability of the complex in vivo, and is necessary for the transcription of many yeast genes. On the basis of these functions, we propose that Tsg2/TAF(II)48p is the
histone
2A-like dimerization partner for the
histone
2B-like TAF(II)68/61p in the yeast TFIID complex.
...
PMID:Identification of a yeast transcription factor IID subunit, TSG2/TAF48. 1075 5
The state of chromatin (the packaging of DNA in eukaryotes) has long been recognized to have major effects on levels of gene expression, and numerous chromatin-altering strategies-including ATP-dependent remodeling and
histone
modification-are employed in the cell to bring about transcriptional regulation. Of these,
histone
acetylation is one of the best characterized, as recent years have seen the identification and further study of many histone acetyltransferase (HAT) proteins and their associated complexes. Interestingly, most of these proteins were previously shown to have coactivator or other transcription-related functions. Confirmed and putative HAT proteins have been identified from various organisms from yeast to humans, and they include Gcn5-related N-acetyltransferase (GNAT) superfamily members Gcn5, PCAF, Elp3, Hpa2, and Hat1: MYST proteins Sas2, Sas3, Esa1, MOF, Tip60, MOZ, MORF, and HBO1; global coactivators p300 and CREB-binding protein; nuclear receptor coactivators SRC-1, ACTR, and TIF2;
TATA-binding protein
-associated factor TAF(II)250 and its homologs; and subunits of RNA polymerase III general factor TFIIIC. The acetylation and transcriptional functions of these HATs and the native complexes containing them (such as yeast SAGA, NuA4, and possibly analogous human complexes) are discussed. In addition, some of these HATs are also known to modify certain nonhistone transcription-related proteins, including high-mobility-group chromatin proteins, activators such as p53, coactivators, and general factors. Thus, we also detail these known factor acetyltransferase (FAT) substrates and the demonstrated or potential roles of their acetylation in transcriptional processes.
...
PMID:Acetylation of histones and transcription-related factors. 1083 22
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