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1.
Mol Biol (Mosk) ; 50(1): 161-73, 2016.
Artigo em Russo | MEDLINE | ID: mdl-27028822

RESUMO

The following hypothesis has been proposed: IF an SNP can significantly increase the expression of an oncogene by increasing the affinity of the TATA-binding protein (TBP) to its promoter, THEN this SNP can also reduce the apparent bioactivity of inhibitors of this oncogene during antitumor chemotherapy and vice versa. In the context of this hypothesis, the previously proposed method (http://beehive.bionet.nsc. ru/cgi-bin/mgs/tatascan/start.pl) was applied to analyze all SNPs found within the [-70; -20] regions (which harbor all proven TBP-binding sites) of the promoters of VEGFA, EGFR, ERBB2, IGF1R, FLT1, KDR, and MET oncogenes according to the human reference genome, hg19. For 83% of these SNPs, their effect on TBP affinity to the oncogene promoters required for assembly of preinitiation complexes was not significant. rs36208385, rs36208384, rs370995111, rs372731987, rs111811434, rs369547510, rs76407893, rs369728300, and rs72001900 can potentially serve as SNP markers to reduce the apparent bioactivity of oncogene inhibitors, while rs141092704, rs184083669, rs145139616, rs200697953, rs187746433, rs199730913, rs377370642, rs114484350, rs374921120, rs146790957, rs376727645, and rs72001900 can be the markers for enhancing this activity.


Assuntos
Antineoplásicos/farmacologia , Regulação Neoplásica da Expressão Gênica/efeitos dos fármacos , Regulação Neoplásica da Expressão Gênica/genética , Neoplasias/genética , Polimorfismo de Nucleotídeo Único , Regiões Promotoras Genéticas/genética , Proteína de Ligação a TATA-Box/metabolismo , Humanos , Neoplasias/tratamento farmacológico , Ligação Proteica/efeitos dos fármacos , Proteínas Proto-Oncogênicas c-met/genética , Receptor ErbB-2/genética , Receptor IGF Tipo 1 , Receptores de Somatomedina/genética , Iniciação da Transcrição Genética/efeitos dos fármacos , Fator A de Crescimento do Endotélio Vascular/genética , Receptor 1 de Fatores de Crescimento do Endotélio Vascular/genética , Receptor 2 de Fatores de Crescimento do Endotélio Vascular/genética
2.
Plants (Basel) ; 12(5)2023 Feb 22.
Artigo em Inglês | MEDLINE | ID: mdl-36903861

RESUMO

For transcription initiation by RNA polymerase II (Pol II), all eukaryotes require assembly of basal transcription machinery on the core promoter, a region located approximately in the locus spanning a transcription start site (-50; +50 bp). Although Pol II is a complex multi-subunit enzyme conserved among all eukaryotes, it cannot initiate transcription without the participation of many other proteins. Transcription initiation on TATA-containing promoters requires the assembly of the preinitiation complex; this process is triggered by an interaction of TATA-binding protein (TBP, a component of the general transcription factor TFIID (transcription factor II D)) with a TATA box. The interaction of TBP with various TATA boxes in plants, in particular Arabidopsis thaliana, has hardly been investigated, except for a few early studies that addressed the role of a TATA box and substitutions in it in plant transcription systems. This is despite the fact that the interaction of TBP with TATA boxes and their variants can be used to regulate transcription. In this review, we examine the roles of some general transcription factors in the assembly of the basal transcription complex, as well as functions of TATA boxes of the model plant A. thaliana. We review examples showing not only the involvement of TATA boxes in the initiation of transcription machinery assembly but also their indirect participation in plant adaptation to environmental conditions in responses to light and other phenomena. Examples of an influence of the expression levels of A. thaliana TBP1 and TBP2 on morphological traits of the plants are also examined. We summarize available functional data on these two early players that trigger the assembly of transcription machinery. This information will deepen the understanding of the mechanisms underlying transcription by Pol II in plants and will help to utilize the functions of the interaction of TBP with TATA boxes in practice.

3.
Vavilovskii Zhurnal Genet Selektsii ; 26(8): 798-805, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36694715

RESUMO

It is generally accepted that during the domestication of food plants, selection was focused on their productivity, the ease of their technological processing into food, and resistance to pathogens and environmental stressors. Besides, the palatability of plant foods and their health benefits could also be subjected to selection by humans in the past. Nonetheless, it is unclear whether in antiquity, aside from positive selection for beneficial properties of plants, humans simultaneously selected against such detrimental properties as allergenicity. This topic is becoming increasingly relevant as the allergization of the population grows, being a major challenge for modern medicine. That is why intensive research by breeders is already underway for creating hypoallergenic forms of food plants. Accordingly, in this paper, albumin, globulin, and ß-amylase of common wheat Triticum aestivum L. (1753) are analyzed, which have been identified earlier as targets for attacks by human class E immunoglobulins. At the genomic level, we wanted to find signs of past negative selection against the allergenicity of these three proteins (albumin, globulin, and ß-amylase) during the domestication of ancestral forms of modern food plants. We focused the search on the TATA-binding protein (TBP)-binding site because it is located within a narrow region (between positions -70 and -20 relative to the corresponding transcription start sites), is the most conserved, necessary for primary transcription initiation, and is the best-studied regulatory genomic signal in eukaryotes. Our previous studies presented our publicly available Web service Plant_SNP_TATA_Z-tester, which makes it possible to estimate the equilibrium dissociation constant (KD) of TBP complexes with plant proximal promoters (as output data) using 90 bp of their DNA sequences (as input data). In this work, by means of this bioinformatics tool, 363 gene promoter DNA sequences representing 43 plant species were analyzed. It was found that compared with non-food plants, food plants are characterized by significantly weaker affinity of TBP for proximal promoters of their genes homologous to the genes of common-wheat globulin, albumin, and ß-amylase (food allergens) (p < 0.01, Fisher's Z-test). This evidence suggests that in the past humans carried out selective breeding to reduce the expression of food plant genes encoding these allergenic proteins.

4.
Genetika ; 46(4): 448-57, 2010 Apr.
Artigo em Russo | MEDLINE | ID: mdl-20536014

RESUMO

Most of more than 11 million experimentally established polymorphisms, accumulated in dbSNP, were identified in the intergenic spacers or coding DNA regions. This fact enables interpretation of the former polymorphisms as neutral, while the latter make clear the biological sense of the associated mutant phenotypes, "the defect of certain proteins". The association of polymorphisms in regulatory DNA regions with mutant phenotypes is poorly studied. Specifically, the defects in certain DNA/protein binding sites were identified in less than 500 cases. In TATA-containing genes of eukaryotes the TATA box, the TBP (TATA-binding protein) binding site, is located about 30 bp upstream from the transcription start site. Interaction between DNA and TBP triggers assemblage of the preinitiation complex. For 37 TATA box polymorphisms in the genes of commercial and laboratory animals and plants, the effect on TBP-binding activity was evaluated using the equilibrium equation for the four subsequent steps of TBP/TATA box binding (nonspecific binding <----> sliding <----> recognition <----> stabilization). According to the GenBank data, these 37 polymorphisms were associated with the changes in a number of selectively valuable traits. Statistically significant congruence of in silico analysis performed with mutant phenotypes (a < 0.05, binomial law) provides suggestion of the mechanism of phenotypic manifestation of these polymorphisms (changing of the TBP-binding activity), as well a validates the possibility of developing the universal test system for experimental-computer prediction of the effects of TATA box mutations in specified genes on selectively valuable traits of the species, varieties, and breeds.


Assuntos
Polimorfismo Genético , Característica Quantitativa Herdável , TATA Box/genética , Proteína de Ligação a TATA-Box/genética , Animais , Bovinos , Bases de Dados Genéticas , Drosophila melanogaster , Camundongos , Ratos , Suínos , Triticum , Zea mays
5.
Biofizika ; 55(3): 400-14, 2010.
Artigo em Russo | MEDLINE | ID: mdl-20586319

RESUMO

Among the main events of transcription initiation of TATA-containing genes in eukayotes are the recognition and binding of the TATA-box by the TATA-binding protein (TBP) to start the preinitiation complex formation on the nucleosomal DNA. Using the equilibrium equation for step-by-step TBP/TATA-binding, we have analyzed 69 experimental datasets on the characteristics of biologicacally important features altered by TATA-box mutations. Among these features, the TBP/TATA-complex parameters, the transcription level, the activity of gene products, yeast colony growth at a dose of growth inhibitor (phenotype), and the heterogenity of the response of a population to unspecific environmental stress have been described. Significant correlations were found between in silico prediction for TBP/TATA affinity and experimental data for in vivo and in vitro test-systems based on 15 cell types of 19 species, RNA polymerases II and III, and natural, recombinant or mutant TBP. Such an invariant impact of the step-by-step TBP/TATA-binding on the biological activity of complex systems, from a molecule to a population, might be due to the fact that TBP/TATA-complex formation precedes specific steps of transcription machinery assembly, which provide the multivariant jigsaw puzzle according to the expression pattern of each eukaryotic gene.


Assuntos
Algoritmos , TATA Box , Proteína de Ligação a TATA-Box/genética , Animais , Humanos , Mutação , Fenótipo , Ligação Proteica , Estresse Fisiológico , Tetraciclinas/farmacologia , Transcrição Gênica , Leveduras/efeitos dos fármacos , Leveduras/genética , Leveduras/crescimento & desenvolvimento
6.
Vavilovskii Zhurnal Genet Selektsii ; 24(7): 785-793, 2020 Nov.
Artigo em Russo | MEDLINE | ID: mdl-33959695

RESUMO

Reproductive potential is the most important conditional indicator reflecting the ability of individuals in a population to reproduce, survive and develop under optimal environmental conditions. As for humans, the concept of reproductive potential can include the level of the individual's mental and physical state, which allows them to reproduce healthy offspring when they reach social and physical maturity. Female reproductive potential has been investigated in great detail, whereas the male reproductive potential (MRP) has not received the equal amount of attention as yet. Therefore, here we focused on the human Y chromosome and found candidate single-nucleotide polymorphism (SNP) markers of MRP. With our development named Web-service SNP_TATA_Z-tester, we examined in silico all 35 unannotated SNPs within 70-bp proximal promoters of the three Y-linked genes, CDY2A, SHOX and ZFY, which represent all types of human Y-chromosome genes, namely: unique, pseudo-autosomal, and human X-chromosome gene paralogs, respectively. As a result, we found 11 candidate SNP markers for MRP, which can significantly alter the TATA-binding protein (TBP) binding affinity for promoters of these genes. First of all, we selectively verified in vitro the values of the TBP-promoter affinity under this study, Pearson's linear correlation between predicted and measured values of which were r = 0.94 (significance p < 0.005). Next, as a discussion, using keyword search tools of the PubMed database, we found clinically proven physiological markers of human pathologies, which correspond to a change in the expression of the genes carrying the candidate SNP markers predicted here. These were markers for spermatogenesis disorders (ZFY: rs1388535808 and rs996955491), for male maturation arrest (CDY2A: rs200670724) as well as for disproportionate short stature at Madelung deformity (e. g., SHOX: rs1452787381) and even for embryogenesis disorders (e. g., SHOX: rs28378830). This indicates a wide range of MRI indicators, alterations in which should be expected in the case of SNPs in the promoters of the human Y-chromosome genes and which can go far beyond changes in male fertility.

7.
Biochemistry (Mosc) ; 74(2): 117-29, 2009 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-19267666

RESUMO

TATA-binding protein (TBP) is the first basal factor that recognizes and binds a TATA box on TATA-containing gene promoters transcribed by RNA polymerase II. Data available in the literature are indicative of admissible variability of the TATA box. The TATA box flanking sequences can influence TBP affinity as well as the level of basal and activated transcription. The possibility of mediated involvement in in vivo gene expression regulation of the TBP interactions with variant TATA boxes is supported by data on TATA box polymorphisms and associated human hereditary pathologies. A table containing data on TATA element polymorphisms in human gene promoters (about 40 mutations have been described), associated with particular pathologies, their short functional characteristics, and manifestation mechanisms of TATA-box SNPs is presented. Four classes of polymorphisms are considered: TATA box polymorphisms that weaken and enhance promoter, polymorphisms causing TATA box emergence and disappearance, and human virus TATA box polymorphisms. The described examples are indicative of the polymorphism-associated severe pathologies like thalassemia, the increased risk of hepatocellular carcinoma, sensitivity to H. pylori infection, oral cavity and lung cancers, arterial hypertension, etc.


Assuntos
Doenças Genéticas Inatas/genética , Polimorfismo de Nucleotídeo Único , TATA Box , Proteína de Ligação a TATA-Box/genética , Predisposição Genética para Doença , Humanos , Mutação , Regiões Promotoras Genéticas , RNA Polimerase II/genética
8.
Mol Biol (Mosk) ; 43(3): 512-20, 2009.
Artigo em Russo | MEDLINE | ID: mdl-19548537

RESUMO

TATA-binding protein (TBP) is a subunit of basal transcription factor TFIID that recognizes and binds to the TATA-box on TATA-containing promoters of class II genes, and starts assembling RNA polymerase II basal transcription complex. It is shown in many works that the sequence of TATA-box with its flanking regions affects the level of basal and activated transcription. TATA-box polymorphisms and human hereditary diseases associated with them show that TBP/TATA interaction may indirectly affect gene regulation in vivo. The object of this work is to determine changes in the TBP/TATA affinity upon polymorphisms in TATA-boxes of human gene promoters. We assess changes in TBP/TATA affinities in silico by using our formula of equilibrium TBP/TATA binding upon four consecutive steps: nonspecific binding <--> sliding <--> braking (stopping) <--> stabilization. Our prognoses agree with known examples of TATA-box polymorphisms and human hereditary diseases associated with them.


Assuntos
Modelos Genéticos , Polimorfismo de Nucleotídeo Único , TATA Box , Proteína de Ligação a TATA-Box/química , Doenças Genéticas Inatas/genética , Predisposição Genética para Doença , Humanos
9.
Kidney Int ; 73(6): 778-81, 2008 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-18185504

RESUMO

Polycystic kidney disease is characterized by the progressive enlargement of kidneys due to expanding fluid-filled cysts with the rate of renal volume increase held to be a marker of disease progression. Magnetic resonance imaging (MRI) is used to monitor changes in renal volume in patients with polycystic kidney disease; however, it has not been effectively used in mice to monitor changes in kidney volume during drug treatment studies. We used a powerful 9.4-T horizontal bore magnetic resonance scanner to track changes in kidney volume in pcy/pcy mice, an ortholog of nephronophthisis type 3. Mice were sequentially scanned from 4 to 30 weeks of age and kidney volumes determined from high-resolution images. Kidney volume and maximal cross-sectional surface area correlated positively with kidney weight and the histologic determination of surface area. The increase in kidney volume was exponential up to 20 weeks of age, after which there was a plateau consistent with the replacement of normal parenchyma by fibrotic tissue. Our study demonstrates that MRI accurately determines the rate of kidney volume increase in mice with polycystic kidney disease and hence may be useful in assessing the effectiveness of therapeutic agents to slow disease progression.


Assuntos
Rim/patologia , Imageamento por Ressonância Magnética , Doenças Renais Policísticas/patologia , Animais , Feminino , Camundongos , Camundongos Endogâmicos , Tamanho do Órgão , Doenças Renais Policísticas/diagnóstico
10.
Mol Biol (Mosk) ; 39(1): 139-46, 2005.
Artigo em Russo | MEDLINE | ID: mdl-15773558

RESUMO

We have analyzed an interaction of the general transcription complex RNA polymerase II proteins (RNA polymerase II, factors TBP, TFIIB, TFIIF, TFIIE and TFIIH) S. cerevisiae with the oligoribonucleotides. With the help of method EMSA was shown that labeled 32P labeled oligoribonucleotide 5'-ACUCUCUUCCGCAUCGC-3' (r-17) binds with the proteins and generates three species of the complexes with the three major shifts. All the three species of the complexes are RNA specific because a total RNA S. cerevisiae was a competitor for all three species but the TATA-containing oligodeoxyribonucleotide (500-fold molar excess) was not a competitor for its. Complexes 32P-r-17 with the proteins belonging to the middle shift are the sequence specific because unlabeled r-17 was a competitor for its binding (100-fold molar excess) but unlabeled UA-rich oligoribonucleotide (5'-AUAUUAUGUUCAAAA-3) was not a competitor for this shift (500-fold molar excess). Complexes belonging to the upper shift are RNA specific probably. We think 32P-r-17 interaction with the proteins belonging to the under shift is nonspecific corresponding to a sorbtion of 32P-r-17 on a protein. The data presented demonstrate that oligoribonucleotide and oligodeoxyribonucleotide don't compete for the binding sites on a basal transcription complex proteins.


Assuntos
Oligorribonucleotídeos/química , RNA Polimerase II/química , Saccharomyces cerevisiae/genética , Proteína de Ligação a TATA-Box/química , Fatores de Transcrição TFII/química , Ensaio de Desvio de Mobilidade Eletroforética , Complexos Multiproteicos/química , Radioisótopos de Fósforo
11.
Bioorg Khim ; 31(4): 372-84, 2005.
Artigo em Russo | MEDLINE | ID: mdl-16119456

RESUMO

Photoactivatable derivatives Ar-NH-(CH2)n-NHpppB (where Ar = p-azidophenyl (A1), 5-azido-2-nitrobenzoyl (A2), or 4-azido-2,3,5,6-tetrafluorobenzoyl (A3) group; B = Ado or Guo; n = 2, 3, or 4) were synthesized. The phosphoroamidate bond stability was found to depend on the structure of both the heterocyclic and the photoactivatable groups. The derivative with A3, Ado, and n=3 is hydrolyzed with regeneration of aryl azide and ATP, whereas the other derivatives are stable in aqueous solutions. The photoanalogues with A1 and A2, B = Ado, and n = 2 or 4 were found to behave as initiating substrates toward the RNA polymerase II from Saccharomyces cerevisiae under the conditions of specific transcription initiation and control of the adenovirus late promoter. The photolysis of N-(4-azidophenyl)-1,4-diaminobutane and N-(5-azido-2-nitrobenzoyl)-1,3-diaminopropane, two functional fragments of the photoaffinity reagents, in aqueous solutions was established to result in the formation of p-benzoquinone diimine and p-nitro-N-arylhydroxylamine derivatives, respectively. The arylhydroxylamine derivatives undergo a number of transformations in aqueous solution leading to nitroso derivatives. We concluded that it is these nitroso derivatives (products of nitrene transformation, rather than the nitrene itself) that may modify proteins with reagents containing p-nitrophenylazide fragment.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/síntese química , Azidas/química , RNA Polimerase II/química , Eletroforese em Gel de Poliacrilamida , Hidroxilaminas/química , Estrutura Molecular , Marcadores de Fotoafinidade , Fotoquímica , RNA Polimerase II/metabolismo , Saccharomyces cerevisiae/enzimologia , Especificidade por Substrato
12.
Nucleosides Nucleotides Nucleic Acids ; 23(6-7): 921-5, 2004 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-15560082

RESUMO

Photoanlogues of the initiation substrates of the RNA polymerase II, N3ArNH(CH2)(n)NHpppA where N3Ar is 5-azido-2-nitrobenzoyl group (n = 2 or 4) were synthesized, allowing the preparation of photoreactive oligonucleotides in situ by RNA polymerase II for application as photolabels. Photolysis of p-nitro-substituted aromatic azide in aqueous medium was investigated. Using the azoxy-coupling reaction it was possible to determine whether a nitrene or p-nitrophenyl hydroxylamine azoxy compound is the trappable intermediate that is generated at ambient temperature in aqueous solution.


Assuntos
Trifosfato de Adenosina/análogos & derivados , Trifosfato de Adenosina/química , Azidas/química , Hidroxilaminas/química , RNA Polimerase II/antagonistas & inibidores , Autorradiografia , Eletroforese em Gel de Poliacrilamida , Fotoquímica , RNA Polimerase II/metabolismo , Especificidade por Substrato
13.
Mol Biol (Mosk) ; 18(3): 637-42, 1984.
Artigo em Russo | MEDLINE | ID: mdl-6206389

RESUMO

It was shown previously, that E. coli RNA polymerase selectively binds certain fractions of oligoribonucleotides with the length greater than or equal to 5 nucleotides from the mixtures of random oligonucleotides of definite length. The data presented demonstrate, that E. coli RNA polymerase from the mixtures of random oligodeoxynucleotides of various length selectively binds oligodeoxynucleotides with the length greater than or equal to 9. The activity of the enzyme correlates with its ability to bind oligodeoxynucleotides. The enzyme which has selectively bound oligodeoxynucleotides, manifests sedimentation position characteristic for E. coli RNA polymerase engaged in transcription. The oligodeoxynucleotides with high affinity to the enzyme act as competitive inhibitors of transcription catalyzed by E. coli RNA polymerase. The data suggest that E. coli RNA polymerase bound oligodeoxynucleotides mimic the nucleotide sequences of the promoter responsible for the binding of the enzyme. It was found that selectively bound oligoribo - and oligodeoxynucleotides do not compete for the site on the enzyme. This property of E. coli RNA polymerase is assumed to play a certain role in the regulation of transcription.


Assuntos
DNA Bacteriano/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Oligodesoxirribonucleotídeos/metabolismo , Oligonucleotídeos/metabolismo , RNA Bacteriano/biossíntese , Ligação Competitiva , Cromatografia DEAE-Celulose , Escherichia coli/metabolismo , Concentração de Íons de Hidrogênio
14.
Mol Biol (Mosk) ; 14(4): 734-42, 1980.
Artigo em Russo | MEDLINE | ID: mdl-6158671

RESUMO

It was shown previously that E. coli RNA polymerase and T7 RNA polymerase being incubated with oligonucleotides of different length derived from RNA endonuclease hydrolysate bind selectively to certain oligonucleotides with the length larger than or equal to 5. The data presented demonstrate that T3 RNA polymerase also binds selectively from the isoplith mixtures certain oligonucleotides starting from pentanucleotides. Adding of excess of T3 RNA polymerase it was possible to exhaustively extract the recognizable oligonucleotides from the isoplith mixture. However, the exhausted by T3 RNA polymerase mixture of pentanucleotides still contained those which are bound selectively by T7 and E. coli RNA polymerases. The data suggest that various RNA-polymerases recognize different oligoribonucleotides. It was shown that T3 DNA inhibits the selective binding of penta-or heptaribonucleotides to T3 RNA polymerase competing obviously for the enzyme. The T3 RNA polymerase bound penta- or heptanucleotides inhibit DNA-dependent RNA synthesis carried out by the enzyme; the isoplith mixtures which do not contain T3 RNA polymerase bound oligonucleotides are deprived of the inhibitory properties. Only those isoplith mixtures contain T3 RNA polymerase bound oligonucleotides which were derived from symmetrically transcribed RNA which have obviously promoter simulating sequences. The data provide evidence that T2 RNA polymerase binds selectively the oligonucleotides mimicking the promotor recognition sites.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/metabolismo , Oligonucleotídeos/metabolismo , Oligorribonucleotídeos/metabolismo , RNA Bacteriano/biossíntese , Fagos T/enzimologia , Sítios de Ligação , Ligação Competitiva , Escherichia coli/enzimologia
15.
Mol Biol (Mosk) ; 12(6): 1313-8, 1978.
Artigo em Russo | MEDLINE | ID: mdl-370554

RESUMO

It was shown previously that E. coli RNA-polymerase being incubated with the random oligonucleotide mixtures of definite length binds certain oligoribonucleotides with the length greater than or equal to 5 nucleotides. The data presented demonstrate that T7 phage induced RNA-polymerase (T7 RNA-polymerase) also binds selectively oligoribonucleotides beginning from pentaribonucleotides. From the random mixtures of penta-, hexa-, hepta-, octa-, nona- and decaribonucleotides the hepta- and octaribonucleotides are bound most efficiently. The T7 RNA-polymerase bound oligoribonucleotides can be completely extracted from the random mixture by the addition of the redundant enzyme amounts. As far as E. coli RNA-polymerase and T7 RNA-polymerase do not compete for the oligoribonucleotides the conclusion is made that they bind different oligoribonucleotides. The addition of the T7 DNA to the previously formed T7 RNA-polymerase--heptaribonucleotide complex competitively displace the heptaribonucleotides from the complex; the competitive effect of T4 DNA is very low. The data suggest that the oligoribonucleotides which are selectively bound by the RNA-polymerase are attached to the enzyme site responsible for the interaction with the promotor.


Assuntos
Colífagos/enzimologia , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Oligorribonucleotídeos , Ligação Proteica , Relação Estrutura-Atividade
16.
Mol Biol (Mosk) ; 22(3): 807-12, 1988.
Artigo em Russo | MEDLINE | ID: mdl-3054500

RESUMO

By using synthetic oligodeoxynucleotides related to the "-10" regions of spc and lacUV5 E. coli promoters we have shown, that the efficient binding occurs with oligodeoxynucleotides non-transcribed DNA strands. The duplexes containing oligodeoxynucleotides from the non-transcribed and transcribed DNA strands are also bound effectively by RNA polymerase. Oligodeoxynucleotides related to the non-transcribed DNA strands can effectively inhibit the RNA synthesis catalyzed by E. coli RNA polymerase. The data obtained allowed to consider the possible mechanism of selective binding of oligodeoxynucleotides by E. coli RNA polymerase and inhibition of the transcription.


Assuntos
Sequência de Bases , RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/genética , Genes Bacterianos , Oligodesoxirribonucleotídeos/metabolismo , Regiões Promotoras Genéticas , Homologia de Sequência do Ácido Nucleico , Escherichia coli/enzimologia , Dados de Sequência Molecular , Oligodesoxirribonucleotídeos/genética , Transcrição Gênica
17.
Mol Biol (Mosk) ; 10(2): 378-85, 1976.
Artigo em Russo | MEDLINE | ID: mdl-781522

RESUMO

RNA polymerase of E. coli (EC 2.7.7.6) is able to bind certain oligoribonucleotides with the length greater than or equal to 5 from the corresponding isoplith mixtures (Knorre V.L., Vasilenko S.V., Salganik R.I., FEBS Letters 30, 229, 1973). It has been shown in this study that all pentaribonucleotides able to be bound by RNA polymerase can be extracted from the random mixture by the enzyme saturation procedure. Loosely and tightly bound pentaribonucleotides subfractions were isolated and each was separated by chromatography into 3-4 isopliths. Blocking of the enzyme SH groups by p-chloromercurium benzoate (10(-3) M) and denaturation by urea (6.3 M) prevent formation of the enzyme-pentaribonucleotides complexes. Complexes are destroyed by heat denaturation. Removal of sigma-subunit does not influence the enzyme capacity for pentaribonucleotides binding.


Assuntos
RNA Polimerases Dirigidas por DNA , Escherichia coli/enzimologia , Oligonucleotídeos , Oligorribonucleotídeos , Catálise , Cloromercurobenzoatos , Temperatura Alta , Íons , Cinética , Desnaturação Proteica , Compostos de Sulfidrila , Ureia
18.
Mol Biol (Mosk) ; 37(5): 893-9, 2003.
Artigo em Russo | MEDLINE | ID: mdl-14593927

RESUMO

Interaction with eukaryotic TATA-binding protein (TBP) was analyzed for natural Escherichia coli RNA polymerase or the recombinant holoenzyme, minimal enzyme, or its sigma subunit. Upon preincubation of full-sized RNA polymerase with TBP and further incubation with a constant amount of 32P-labeled phosphamide derivative of a TATA-containing oligodeoxyribonucleotide, the yield of the holoenzyme-oligonucleotide covalent complex decreased with increasing TBP concentration. This was considered as indirect evidence for complexing of RNA polymerase with TBP. In gel retardation assays, the holoenzyme, but neither minimal enzyme nor the sigma subunit, interacted with TPB, since the labeled probe formed complexes with both proteins in the reaction mixture combining TBP with the minimal enzyme or the sigma subunit. It was assumed that E. coli RNA polymerase is functionally similar to eukaryotic RNA polymerase II, and that the complete ensemble of all subunits is essential for the specific function of the holoenzyme.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/enzimologia , Proteína de Ligação a TATA-Box/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Primers do DNA , Dados de Sequência Molecular , Ligação Proteica , Homologia de Sequência de Aminoácidos
19.
Mol Biol (Mosk) ; 27(1): 64-71, 1993.
Artigo em Russo | MEDLINE | ID: mdl-7683372

RESUMO

It was shown previously that E. coli RNA polymerase in a highly selective manner recognizes and binds 11-14-mere oligodeoxyribonucleotides related to the "-10" region of the nontranscribed DNA strand of bacterial gene promoters. The oligodeoxyribonucleotides cover the Pribnow box with flanking nucleotides up to the transcription start. These affinity oligodeoxyribonucleotides inhibit competitively the transcription of bacterial DNA carried out by E. coli RNA polymerase. The present work has demonstrated that E. coli RNA polymerase is not capable of binding the oligoribonucleotides homologous to the affinity oligodeoxyribonucleotides related to the "-10" area of the spc promoter, but binds the oligoribonucleotides which are complementary to the latter. The oligoribonucleotides with a high affinity for the E. coli RNA polymerase strongly inhibit transcription of the bacterial DNA. Attachment of alkylating groups to the 5'-ends of the affinity oligodeoxy- and oligoribonucleotides provides their covalent binding to the E. coli RNA polymerase subunits. It was shown that the modified affinity 32P-labelled oligodeoxyribonucleotide is covalently bound to the sigma-subunit while the modified affinity 32P-labelled oligoribonucleotide is covalently bound to the beta'beta-subunits of the E. coli RNA polymerase. It is suggested that the affinity oligoribonucleotides can be transcribed from the non-transcribed DNA strand in the region of the open complex and functions presumably as a primer which is splitted later from the nascent RNA or as a regulator of transcription.


Assuntos
RNA Polimerases Dirigidas por DNA/metabolismo , Escherichia coli/metabolismo , Oligonucleotídeos/metabolismo , Regiões Promotoras Genéticas , Sequência de Bases , Sítios de Ligação , DNA Bacteriano/genética , Escherichia coli/genética , Dados de Sequência Molecular , RNA Bacteriano/genética , Transcrição Gênica
20.
Acta Naturae ; 6(2): 36-40, 2014 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25093109

RESUMO

The TATA-binding protein (TBP) is a key part of the transcription complex of RNA polymerase II. Alone or as a part of the basal transcription factor TFIID, TBP binds the TATA box located in the core region of the TATA-containing promoters of class II genes. Previously, we studied the effects of single nucleotide polymorphisms (SNPs) on TBP/TATA-box interactions using gel retardation assay. It was demonstrated that most SNPs in the TATA boxes of some human gene promoters cause a 2- to 4-fold decrease in TBP/TATA affinity, which is associated with an increased risk of hereditary diseases, such as ß thalassemias of diverse severity, hemophilia B Leyden, myocardial infarction, thrombophlebitis, lung cancer, etc. In this work, the process of TBP/TATA complex formation has been studied in real time by a stopped-flow technique using recombinant human TBP and duplexes, which were identical to the TATA box of the wild-type and a SNP-containing triosephosphate isomerase gene promoter and were fluorescently labeled by the Cy3/Cy5 FRET pair. It has been demonstrated for the first time that real-time binding of TBP to the TATA box of the TPI gene promoter is complete within 10 s and is described by a single-stage kinetic model. The complex formation of TBP with the wild-type TATA box occurs 5.5 times faster and the complex dissociation occurs 31 times slower compared with the SNPcontaining TATA box. Within the first seconds of the interaction, TBP binds to and simultaneously bends the TATA box. Importantly, the TATA box of the wild-type TPI gene promoter requires lower TBP concentrations compared to the TATA box containing the -24T → G SNP, which is associated with neurological and muscular disorders, cardiomyopathy, and other diseases.

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