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1.
Mol Biol (Mosk) ; 26(5): 1134-47, 1992.
Artigo em Russo | MEDLINE | ID: mdl-1470178

RESUMO

Abnormalities of some oncogenes, antioncogenes and losses of heterozygosity (LOH) of chromosome 11p, 17p, and 17q in colorectal carcinomas (CC) was studied. Amplification of ERBB-1/HER-1 oncogene was detected in 2 of 56 cases; ERBB-2/HER-2- in 4 of 62. There was a lack of evidence for C-MYC oncogene amplification (67 cases). LOH of chromosome 11p (HRAS-1 probe) was found in 2 of 37 informative (heterozygous) cases; such events were not accompanied by point mutations in "hot" codons (12th or 61st) in the remaining allele. Prevalence of A3 and A4 alleles of HRAS-1 oncogene (68 cases) as compared to healthy donors was noted. RB-1 (41 cases) and p53 (62 cases) suppressor genes did not show any alterations in Southern-blot analysis. LOH of chromosome 17p (YNZ-22 probe) was found in 15 of 26 heterozygous CC; 17q (THH-59 probe)--in 4 of 16. Analysis of 175th codon of p53 gene revealed only one case of mutation in 35 CC studied. Finally, we were able to detect genetic alterations in 23 of 40 (58%) CC, that were studied on each parameter using Southern-blot. We failed to find any correlation between various molecular abnormalities or clinical characteristics. The data obtained are in disagreement with the view concerning frequent involvement of p53 antioncogene in chromosome 17p deletions.


Assuntos
Cromossomos Humanos Par 17 , Neoplasias do Colo/genética , Deleção de Genes , Genes Supressores de Tumor , Oncogenes , Proteínas Proto-Oncogênicas/genética , Sequência de Bases , Southern Blotting , Genes myc , Genes p53 , Genes ras , Heterozigoto , Humanos , Dados de Sequência Molecular , Oligonucleotídeos , Plasmídeos , Reação em Cadeia da Polimerase , Células Tumorais Cultivadas
2.
Bioorg Khim ; 12(1): 116-23, 1986 Jan.
Artigo em Russo | MEDLINE | ID: mdl-3004511

RESUMO

In the course of studying extrachromosomal DNA with composite replicons, a hybrid has been constructed by the in vitro recombination of the filamentous phage M13mp2 DNA (RF) and plasmid pUR222 (ApR). Both parental DNAs contain a fragment of lac-operon (ca. 800 bp), which includes the distal end of lacI gene, lacPO segments, and the lacZ gene proximal region coding for 145 N-terminal amino acid residues of beta-galactosidase and thus providing for alpha-complementation, the effect being cancelled with a polynucleotide insertion at the unique EcoRI site in the lacZ gene segment. E. coli BMH71-18 cells were transformed with the ligated mixture of EcoRI restricts of both DNAs. A phage-like nucleoprotein was isolated from colourless plaques (on the Xgal- and IPTG-supplemented medium); its deproteinization yielded a DNA which contains the ApR-determinant and, according to PAGE, structurally specific staining, restriction analysis, sequencing by the Sanger procedure, and electron microscopy data, is a linear double-stranded molecule comprising the phage and plasmid genomes in an equimolar ratio. Since the hybrid DNA does not display the alpha-complementation effect, both bacterial inserts are in the opposite orientation. Transformation of both phage (F+) and plasmid (F-) hosts with the hybrid DNA led to cultures which, after precipitation of the nucleoprotein from the extracellular medium and deproteinization, afforded the same composite DNA.(ABSTRACT TRUNCATED AT 250 WORDS)


Assuntos
Colífagos/análise , DNA Recombinante/isolamento & purificação , DNA Viral/análise , Hibridização de Ácido Nucleico , Plasmídeos , Mapeamento Cromossômico , Colífagos/genética , Enzimas de Restrição do DNA , DNA Circular/análise , DNA Circular/genética , DNA Recombinante/análise , DNA Viral/genética , Eletroforese em Gel de Ágar
3.
Bioorg Khim ; 9(5): 711-3, 1983 May.
Artigo em Russo | MEDLINE | ID: mdl-6237658

RESUMO

A recombination site in the transducing bacteriophage lambda plac5 DNA has been structurally elucidated. Comparison of primary structures of E. coli lac-operon (distal end of lacZ gene, Z-Y spacer, and proximal end of lacY gene) described earlier with corresponding segments of bacteriophages lambda CI857 and lambda plac 5-2 DNAs sequenced in this paper showed that the bacterial DNA insert ends immediately after Z-Y spacer, just before the initiating triplet ATG of lacY gene. It thus follows that in contrast to the earlier conception, the insert does not seem to include any part of lacY gene. The recombination sites in both phage and bacterial DNA contain structurally homological segments about 20 b. p. long (crossover region), with two extra basepairs in the bacterial DNA (AT in the sense-strand). We suppose that the very dinucleotide plays a substantial role in initiation of recombinational event: causing formation of a nonperfect heteroduplex structure, it determines the T-A internucleotide bond to be endonucleolytically cut (crossover point) followed by exonucleolytic elimination of the extra links (AT) and reciprocal strand exchange. The second recombination site in lambda plac5 DNA has been localized by us within lacI gene as being close to the HindII site (nucleotides 854 to 859 of the gene). The structures of the two regions of site-specific recombination may shed light upon mechanisms of the phage abnormal excision leading to formation of transducing phages.


Assuntos
Bacteriófago lambda/genética , DNA Viral/genética , Óperon Lac , Recombinação Genética , Transdução Genética , Sequência de Bases , DNA Bacteriano/genética , Escherichia coli/genética
4.
Bioorg Khim ; 12(5): 640-6, 1986 May.
Artigo em Russo | MEDLINE | ID: mdl-3015153

RESUMO

Interaction of the restriction endonuclease BamHI with a series of synthetic oligodeoxynucleotides containing the restriction site has been studied. The enzyme is shown to specifically cut the BamHI site in hexanucleotide (I) and in non-selfcomplementary deca- and octanucleotides (II)-(IV). The data obtained led to the conclusion that BamHI reacts with duplex structures, while playing an important role in their stabilization. In 14-mer (V) BamHI cuts a non-standard half-site GAA to yield the 5'-terminal tri- (rather than hepta-) nucleotide. Hypothetical mechanisms of the process are discussed basing on conception of the role of higher DNA structures in the interaction with restriction endonucleases.


Assuntos
Enzimas de Restrição do DNA/metabolismo , Oligodesoxirribonucleotídeos/metabolismo , Sequência de Bases , Desoxirribonuclease BamHI , Eletroforese em Gel de Poliacrilamida , Técnicas In Vitro , Substâncias Macromoleculares , Conformação de Ácido Nucleico , Oligodesoxirribonucleotídeos/síntese química
5.
Bioorg Khim ; 12(5): 695-8, 1986 May.
Artigo em Russo | MEDLINE | ID: mdl-3015155

RESUMO

In studying molecular mechanisms of specialized transduction, primary structure of the junction between the E. coli gene lacI and the lambda phage locus Ea47 in transducing bacteriophage lambda plac5 has been established. Along with the lambda DNA and E. coli lac operon structures as well as with our earlier data on another phage-bacterial junction in lambda plac5, it lead to the complete sequence of lambda plac5 DNA, including the lac5 substitution, a wellknown segment of lambdoid cloning vehicles. The lambda plac5 DNA is shown to consist of 48645 b.p. distributed as follows: 19368 (lambda left arm) + 3924 (lac5 substitution) + 25353 (lambda right arm). The presence of the phage pbL promoter near to the right end of the lac5 insert is shown. The lacI gene distal end in lambda plac5 proved to be considerably more long-stretched than it used to be believed, coding for 224 C-terminal amino-acid residues of lac repressor. The recombination studied in this paper, similarly to the abnormal prophage excision, occurred near to a Chi-like structure, which is partly homologous to the chi+lacZ site present in lambda plac5. On the basis of the data obtained, a key role of the E. coli RecBC system and Chi sites in the formation of long-stretched deletions in the bacterial cell has been suggested.


Assuntos
Bacteriófago lambda/genética , DNA Viral/genética , Genes Virais , Transdução Genética , Sequência de Bases , Enzimas de Restrição do DNA , DNA Bacteriano/genética , Escherichia coli/enzimologia , Escherichia coli/genética
6.
Bioorg Khim ; 27(6): 462-5, 2001.
Artigo em Russo | MEDLINE | ID: mdl-11811071

RESUMO

A functional (dihydroxybutyl) derivative of p-(2-benzoxazolyl)tolane, a fluorescent label novel for biopolymers, was synthesized. The functionalized solid support obtained on its basis was employed in the synthesis of oligodeoxynucleotides 3-terminally labeled with benzoxazolyltolane (these oligonucleotides also contained 1-phenylethynylpyrene residues). This fluorophore within its dihydroxybutyl derivative and the oligonucleotides modified with it displays an intensive fluorescence characterized by a high Stokes shift. The oligonucleotides labeled with this fluorophore are potential probes sensitive to the biopolymer microenvironment.


Assuntos
Corantes Fluorescentes/síntese química , Oligonucleotídeos/síntese química , Oxazóis/química , Fluorescência , Corantes Fluorescentes/química , Oligonucleotídeos/química
7.
Bioorg Khim ; 14(3): 333-9, 1988 Mar.
Artigo em Russo | MEDLINE | ID: mdl-2454631

RESUMO

Interaction of MspI restriction endonuclease with a series of oligodeoxynucleotides, varying in stability of secondary structure and in location of the restriction site, has been studied. It is shown that a functionally active MspI-site must be double-stranded and flanked from both sides. Separate MspI-cleavage of dodecanucleotides dCGACCCGGGATC and dGATCCCGGGTCG is inhibited by the reaction products as well as by non-homological hexanucleotides dGGTACC and dGGATCC (but not by dCGGCGC). Polyethylene glycol in low concentrations (1-3%) promotes and in higher concentrations (7-14%) inhibits the cleavage. A scheme of MspI functioning is suggested including enzyme's step-by-step recognition of the restriction site and its nonspecific interaction with flanking segments of DNA, which leads to formation of the productive complex.


Assuntos
Enzimas de Restrição do DNA/metabolismo , Oligodesoxirribonucleotídeos/metabolismo , Sequência de Bases , Sítios de Ligação , Desoxirribonuclease HpaII , Eletroforese em Gel de Poliacrilamida , Ácidos Nucleicos Heteroduplexes , Oligodesoxirribonucleotídeos/síntese química , Conformação Proteica , Especificidade por Substrato
8.
Bioorg Khim ; 15(7): 997-1000, 1989 Jul.
Artigo em Russo | MEDLINE | ID: mdl-2530989

RESUMO

Investigating molecular mechanism of illegitimate recombinations in prokaryote we study transducing bacteriophages of the lambda lac series. We have carried out physical mapping of bacteriophage lambda plac9 DNA and, by comparing the obtained results with the data on the structure of lambda DNA and lac operon of E. coli, located the phage-bacterial junction corresponding to the lambda-lac9 abnormal excision and elucidated the nucleotide sequence around the junction. It led to the primary structure of phage and bacterial segments in the lysogenic bacterium which took part in the recombinational act leading to the abnormal excision and lambda lac9 formation. Structural homology of the partners in the lambda plac9 excision proved to be lower than in case of the earlier studied lambda plac5 and lambda plac10 whose excision proceeded regioselectively. Various aspects of the crossover area, including the crossover point's probable position and enzymic systems participating in the abnormal excision, are discussed.


Assuntos
Bacteriófago lambda/genética , Deleção Cromossômica , Recombinação Genética , Transdução Genética , Sequência de Bases , DNA Viral/genética , Eletroforese em Gel de Ágar , Dados de Sequência Molecular
9.
Bioorg Khim ; 25(11): 838-47, 1999 Nov.
Artigo em Russo | MEDLINE | ID: mdl-10645489

RESUMO

Recent data are reviewed on the employment of fluorescence resonance energy transfer (FRET) in studying hybridization and higher structures of nucleic acids as well as their enzyme- and ribozyme-catalyzed reactions.


Assuntos
Ácidos Nucleicos/química , Espectrometria de Fluorescência , Sequência de Bases , Catálise , Conformação de Ácido Nucleico , RNA Catalítico/metabolismo
10.
Bioorg Khim ; 16(11): 1570-3, 1990 Nov.
Artigo em Russo | MEDLINE | ID: mdl-2096829

RESUMO

Mixture of polyadenylated mRNAs from human monocytes has been subjected to the reverse transcription specifically initiated from the mRNA encoding interleukin 1 alpha by a synthetic polynucleotide complementary to the mRNA's coding 3'-end to yield the corresponding mRNA-cDNA duplex. Under conditions of the polymerase chain reaction, with the above polynucleotide as a downstream primer and an upstream primer corresponding to the beginning of the mature interleukin 1 alpha (AA 113-271) gene, the mRNA-cDNA duplex yielded the desired gene, whose structure was proved by the restriction and sequence analyses. The gene, containing translation initiation and termination triplets, can be used for producing interleukin 1 alpha in various expression systems and as a probe in studies of the lymphokine's biosynthesis. This method of the gene synthesis does not need construction and analysis of cDNA libraries nor synthesis of double-stranded DNA, and can, in principle, make use of the total (non-fractionated) cellular RNA.


Assuntos
DNA/genética , Amplificação de Genes , Genes Sintéticos , Interleucina-1/genética , RNA Mensageiro/genética , Sequência de Bases , Clonagem Molecular , Sondas de DNA , Eletroforese em Gel de Ágar , Humanos , Dados de Sequência Molecular , Ácidos Nucleicos Heteroduplexes , Plasmídeos , Biossíntese de Proteínas , Transcrição Gênica
12.
Bioorg Khim ; 18(2): 217-25, 1992 Feb.
Artigo em Russo | MEDLINE | ID: mdl-1605799

RESUMO

An approach to the directed genetic recombination in vitro has been devised, which allows for joining, in a predetermined chemical-enzymatic way, a series of DNA segments to give a precisely spliced polynucleotide sequence (DNA Splicing by Directed Ligation, SDL). The approach makes use of amplification, by several polymerase chain reactions (PCR), of the chosen DNA segments. The corresponding primers contain recognition sites of the class IIS restriction endonucleases, yielding protruding ends of unique primary structures. The protruding ends of the segments to be joined together are structurally predetermined to make them mutually complementary. Ligation of the mixture of the segments so synthesized gives the desired sequence in an unambiguous way. The suggested approach has been exemplified by the synthesis of a totally processed (intronless) gene encoding human mature interleukin-1 alpha.


Assuntos
DNA/metabolismo , Sequência de Bases , Clonagem Molecular , Eletroforese em Gel de Poliacrilamida , Éxons , Amplificação de Genes , Humanos , Interleucina-1/genética , Dados de Sequência Molecular , Plasmídeos , Reação em Cadeia da Polimerase , Recombinação Genética
13.
Bioorg Khim ; 26(1): 39-50, 2000 Jan.
Artigo em Russo | MEDLINE | ID: mdl-10806551

RESUMO

Novel reagents for the fluorescent labeling of oligo- and polynucleotides have been prepared: 5-(1-pyrenylethynyl)-2'-deoxyuridine 3'-phosphoramidite and a solid support carrying this nucleoside. Oligonucleotides containing one or several modified units have been synthesized, and the fluorescence of these probes has been shown to change upon hybridization with the complementary sequence.


Assuntos
Corantes Fluorescentes/química , Oligodesoxirribonucleotídeos/química , Oligodesoxirribonucleotídeos/síntese química , Pirenos/química , Uridina/análogos & derivados , Uridina/química
14.
Bioorg Khim ; 29(3): 290-5, 2003.
Artigo em Russo | MEDLINE | ID: mdl-12845804

RESUMO

5-(3-Perylenylethynyl)-2'-deoxyuridine was prepared by cross-linking 5-iodo-2'-deoxyuridine derivatives with 3-ethynylperylene followed by deprotection. 5-(1-Perylenylethynyl)-, 5-(3-perylenylethynyl)-, and 5-[4-(2-benzoxazolyl)phenylethynyl]-2'-deoxyuridine were found to inhibit in Vero cells the replication of type 1 herpes simplex virus and its drug-resistant strains.


Assuntos
Antivirais/química , Antivirais/farmacologia , Desoxiuridina/química , Animais , Células Cultivadas , Química Orgânica/métodos , Reagentes de Ligações Cruzadas/química , Desoxiuridina/análogos & derivados , Avaliação Pré-Clínica de Medicamentos/métodos , Farmacorresistência Viral Múltipla , Herpesvirus Humano 1/efeitos dos fármacos , Herpesvirus Humano 1/fisiologia , Rim/citologia , Rim/efeitos dos fármacos , Rim/virologia , Perileno/análogos & derivados , Perileno/química , Relação Estrutura-Atividade , Replicação Viral/efeitos dos fármacos
15.
Bioorg Khim ; 20(12): 1334-41, 1994 Dec.
Artigo em Russo | MEDLINE | ID: mdl-7695651

RESUMO

In a search for new restriction endonucleases type II, among forty bacterial strains of the Bacillus genus two strains producing site-specific endonucleases have been found. Endonucleases BbvAIII and BspFI, isolated from B. brevis BLM B-677 and B. species F, are shown to be true isoschisomers of BspMII (Kpn2I) and Sau3AI, respectively.


Assuntos
Bacillus/enzimologia , Desoxirribonucleases de Sítio Específico do Tipo II/isolamento & purificação , Bacteriófago lambda/genética , Sequência de Bases , Cromatografia por Troca Iônica , DNA Viral/metabolismo , Desoxirribonucleases de Sítio Específico do Tipo II/metabolismo , Eletroforese em Gel de Ágar , Eletroforese em Gel de Poliacrilamida , Hidrólise , Dados de Sequência Molecular
16.
Bioorg Khim ; 23(1): 33-41, 1997 Jan.
Artigo em Russo | MEDLINE | ID: mdl-9139641

RESUMO

N-[2-(1-pyrenyl)ethyl]-1-pyrenylacetamide, bis[2-(1-pyrenyl)ethyl]amine, and N,N-bis[2-(1-pyrenyl)ethyl]succinamide were synthesized from 1-pyrenylacetic acid. These compounds contain adjacent pyrene residues and display excimer fluorescence. The latter compound, as a pentafluorophenyl ester, was used to prepare fluorescently labeled oligodeoxyribonucleotide (5)CAGGAAACAGCTATGAC. For N,N-bis[2-(1-pyrenyl)ethyl]succinamide, the excimer-to-monomer fluorescence ratio and intensity of fluorescence in water-methanol solutions changed in the presence of single-stranded and double-stranded oligonucleotides, upon attachment to an oligonucleotide, and upon hybridization of the resulting conjugate with the complementary nucleotide sequence.


Assuntos
Corantes Fluorescentes/química , Pirenos/química , Cromatografia Líquida de Alta Pressão , Sondas de Oligonucleotídeos , Espectrometria de Fluorescência
17.
Bioorg Khim ; 15(7): 1001-2, 1989 Jul.
Artigo em Russo | MEDLINE | ID: mdl-2530988

RESUMO

Molecular nature of two beta 0-thalassaemia-causing mutations in beta-globin gene in Azerbaijanian population has been elucidated, viz., C-T transition in 39 codon (nonsense mutation) and previously unknown G deletion in 82/83 codons.


Assuntos
Globinas/genética , Mutação , Talassemia/genética , Azerbaijão , Códon , Eletroforese em Gel de Poliacrilamida , Humanos
18.
Bioorg Khim ; 15(12): 1690-2, 1989 Dec.
Artigo em Russo | MEDLINE | ID: mdl-2634967

RESUMO

Upon amplification in vitro of the 12th exon area of the human phenylalanine hydroxylase gene followed by allele-specific hybridisation of the amplification product with synthetic probes and its sequencing by the Maxam-Gilbert method, a C----T transition causing phenylketonuria has been identified in Latvian patients.


Assuntos
Éxons , Mutação , Fenilalanina Hidroxilase/genética , Fenilcetonúrias/genética , Alelos , Sequência de Bases , DNA/genética , Humanos , Dados de Sequência Molecular , Hibridização de Ácido Nucleico , Fenilcetonúrias/enzimologia
19.
Genetika ; 29(5): 820-4, 1993 May.
Artigo em Russo | MEDLINE | ID: mdl-8335239

RESUMO

Prenatal DNA-diagnosis of beta-thalassemia in a family from Azerbaijan revealed two mutations new for this region--G-A transition at codon 15 and G-C transversion at position 5 of the intron 1. Prenatal diagnosis was carried out by direct sequencing of in vitro amplified (PCR) beta-globin gene fragments with a modified Sanger technique using thermostable DNA polymerase. The absence of parents mutations in the fetal DNA allowed us to conclude that the fetus is normal. The diagnosis was proved at hematological testing of the baby borne.


Assuntos
Triagem de Portadores Genéticos/métodos , Mutação , Diagnóstico Pré-Natal/métodos , Talassemia beta/genética , Azerbaijão/epidemiologia , Sequência de Bases , Códon , Feminino , Marcadores Genéticos , Globinas/genética , Humanos , Masculino , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Polimorfismo Genético , Gravidez , Talassemia beta/prevenção & controle
20.
Genetika ; 31(4): 528-31, 1995 Apr.
Artigo em Russo | MEDLINE | ID: mdl-7607439

RESUMO

The polymorphism of Alu-repeats, which are located in the introns of the human factor IX gene (copies 1-3), was studied. To identify polymorphic variants, direct sequencing of PCR products that contained appropriate repeats was used. In each case, 20 unrelated X chromosomes were studied. A polymorphic Dra I site was found near the 3'-end of Alu copy 3 within the region of the polyA tract. A PCR-based testing system with internal control of restriction hydrolysis was suggested. Testing 81 unrelated X chromosomes revealed that the frequency of the polymorphic Dra I site is 0.23. Taq I polymorphism, which was revealed in Alu copy 4 of factor IX gene in our previous work, was found to be closely linked to Dra I polymorphism. Studies in linkage between different types of polymorphisms of the factor IX gene revealed the presence of a rare polymorphism in intron A that was located within the same minisatellite region as the known polymorphic insertion 50bp/Dde I. However, the size of the insertion in our case was 26 bp. Only one polymorphic variant was found among over 150 unrelated X chromosomes derived from humans from Moscow and its vicinity.


Assuntos
DNA Satélite/genética , Fator IX/genética , Polimorfismo Genético , Sequência de Bases , Ligação Genética , Humanos , Íntrons , Dados de Sequência Molecular , Reação em Cadeia da Polimerase , Sequências Repetitivas de Ácido Nucleico , Cromossomo X
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