25 results on '"Beresten S"'
Search Results
2. Studies of seryl-tRNA-synthetase from the bovine liver by the immunochemical methods
- Author
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Sidorik, L. L., primary, Gudzera, O. I., additional, Zolotukhina, I. M., additional, Dragovoz, V. A., additional, Tukalo, M. A., additional, Beresten, S. F., additional, and Matsuka, G. Kh., additional
- Published
- 1990
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3. Immunoelectron-microscopic study of seryl-tRNA-synthetase localization in cells of higher eucaryotes
- Author
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Sidorik, L. L., primary, Popenko, V. I., additional, Cherny, N. E., additional, Tukalo, M. A., additional, Beresten, S. F., additional, and Matsuka, G. Kh., additional
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- 1990
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4. A method for selection of hybridomas, secreting monoclonal antibodies against tyrosyl-tRNA synthetase, based on monitoring of the enzymatic activity
- Author
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Ribkinska, T. A., primary, Vartanyan, O. A., additional, Filonenko, V. V., additional, Sidorik, L. L., additional, Kornelyuk, A. I., additional, and Beresten, S. F., additional
- Published
- 1990
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5. Characterization of the human and mouse WRN 3'-->5' exonuclease.
- Author
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Huang, S, Beresten, S, Li, B, Oshima, J, Ellis, N A, and Campisi, J
- Abstract
Werner's syndrome (WS) is an autosomal recessive disorder in humans characterized by the premature development of a partial array of age-associated pathologies. WRN, the gene defective in WS, encodes a 1432 amino acid protein (hWRN) with intrinsic 3'-->5' DNA helicase activity. We recently showed that hWRN is also a 3'-->5' exonuclease. Here, we further characterize the hWRN exonuclease. hWRN efficiently degraded the 3' recessed strands of double-stranded DNA or a DNA-RNA heteroduplex. It had little or no activity on blunt-ended DNA, DNA with a 3' protruding strand, or single-stranded DNA. The hWRN exonuclease efficiently removed a mismatched nucleotide at a 3' recessed terminus, and was capable of initiating DNA degradation from a 12-nt gap, or a nick. We further show that the mouse WRN (mWRN) is also a 3'-->5' exonuclease, with substrate specificity similar to that of hWRN. Finally, we show that hWRN forms a trimer and interacts with the proliferating cell nuclear antigen in vitro. These findings provide new data on the biochemical activities of WRN that may help elucidate its role(s) in DNA metabolism.
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- 2000
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6. Search for potential gastric cancer markers using miRNA databases and gene expression analysis
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Volkomorov V, Grigoryeva E, Krasnov G, Litviakov N, Tsyganov M, Karbyshev M, Zavyalova M, Afanasуev S, Cherdyntseva N, Nikolai Lisitsyn, and Beresten S
- Subjects
Male ,Extracellular Matrix Proteins ,Reverse Transcriptase Polymerase Chain Reaction ,Original contributions ,Gene Expression Profiling ,Connective Tissue Growth Factor ,Down-Regulation ,Gene Expression ,Cell Differentiation ,Middle Aged ,Up-Regulation ,Fibroblast Growth Factors ,Gene Expression Regulation, Neoplastic ,MicroRNAs ,Gastric Mucosa ,Stomach Neoplasms ,Wnt4 Protein ,Lymphatic Metastasis ,Biomarkers, Tumor ,Humans ,Female ,RNA, Messenger ,Databases, Nucleic Acid ,Heparan Sulfate Proteoglycans ,Cell Proliferation - Abstract
Aim: The aim of this study was to identify genes that are differentially expressed in gastric tumors and to analyze the association of their expression level with tumor clinicopathologic features. Methods: In the present research, we used bioinformatic-driven search to identify miRNA that are down-regulated in gastric tumors and to find their potential targets. Then, the expression levels of some of the target mRNAs were investigated using reverse transcription polymerase chain reaction (RT-PCR) analysis. Results: As a result of the bioinformatics analysis, fifteen genes were found to be potentially differentially expressed between the tumors and normal gastric tissue. Five of them were chosen for the further analysis (WNT4, FGF12, EFEMP1, CTGF, and HSPG2) due to their important role in cell proliferation and differentiation. Expression levels of these genes were evaluated in our collection of frozen tissue samples of gastric tumor and paired normal stomach epithelia. Increased FGF12 expression was observed in diffuse type of gastric cancer while WNT4 mRNA was found to be down-regulated in intestinal type of gastric cancer. Besides, CTGF gene overexpression was revealed in diffuse type of stomach cancer in comparison with that in intestinal type. Up-regulation of CTGF was also associated with lymph node metastasis. Conclusions: The findings show its expedient to perform further investigations in order to clarify diagnostic and prognostic value of CTGF, FGF12, and WNT4’s in stomach cancer as well as the role of these genes in carcinogenesis.
7. Localization of antigenic determinants of beef tryptophanyl-tRNA synthetase revealed by monoclonal antibodies
- Author
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Beresten, S. F., primary, Rubikaite, B. I., additional, and Kazakov, V. K., additional
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- 1987
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8. Enteric alpha defensins in norm and pathology
- Author
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Lisitsyn Nikolai A, Bukurova Yulia A, Nikitina Inna G, Krasnov George S, Sykulev Yuri, and Beresten Sergey F
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Enteric alpha defensins ,Paneth cells ,innate immunity ,IBD ,colon cancer ,Therapeutics. Pharmacology ,RM1-950 ,Infectious and parasitic diseases ,RC109-216 ,Microbiology ,QR1-502 - Abstract
Abstract Microbes living in the mammalian gut exist in constant contact with immunity system that prevents infection and maintains homeostasis. Enteric alpha defensins play an important role in regulation of bacterial colonization of the gut, as well as in activation of pro- and anti-inflammatory responses of the adaptive immune system cells in lamina propria. This review summarizes currently available data on functions of mammalian enteric alpha defensins in the immune defense and changes in their secretion in intestinal inflammatory diseases and cancer.
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- 2012
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9. Search for potential gastric cancer markers using miRNA databases and gene expression analysis.
- Author
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Volkomorov V, Grigoryeva E, Krasnov G, Litviakov N, Tsyganov M, Karbyshev M, Zavyalova M, Afanasуev S, Cherdyntseva N, Lisitsyn N, and Beresten S
- Subjects
- Biomarkers, Tumor metabolism, Cell Differentiation genetics, Cell Proliferation, Connective Tissue Growth Factor biosynthesis, Connective Tissue Growth Factor genetics, Databases, Nucleic Acid, Down-Regulation, Extracellular Matrix Proteins biosynthesis, Extracellular Matrix Proteins genetics, Female, Fibroblast Growth Factors biosynthesis, Fibroblast Growth Factors genetics, Gene Expression, Gene Expression Profiling, Gene Expression Regulation, Neoplastic, Heparan Sulfate Proteoglycans biosynthesis, Heparan Sulfate Proteoglycans genetics, Humans, Lymphatic Metastasis genetics, Male, Middle Aged, RNA, Messenger biosynthesis, Reverse Transcriptase Polymerase Chain Reaction, Up-Regulation, Wnt4 Protein biosynthesis, Wnt4 Protein genetics, Biomarkers, Tumor genetics, Gastric Mucosa metabolism, MicroRNAs genetics, Stomach Neoplasms genetics, Stomach Neoplasms metabolism
- Abstract
Aim: The aim of this study was to identify genes that are differentially expressed in gastric tumors and to analyze the association of their expression level with tumor clinicopathologic features., Methods: In the present research, we used bioinformatic-driven search to identify miRNA that are down-regulated in gastric tumors and to find their potential targets. Then, the expression levels of some of the target mRNAs were investigated using reverse transcription polymerase chain reaction (RT-PCR) analysis., Results: As a result of the bioinformatics analysis, fifteen genes were found to be potentially differentially expressed between the tumors and normal gastric tissue. Five of them were chosen for the further analysis (WNT4, FGF12, EFEMP1, CTGF, and HSPG2) due to their important role in cell proliferation and differentiation. Expression levels of these genes were evaluated in our collection of frozen tissue samples of gastric tumor and paired normal stomach epithelia. Increased FGF12 expression was observed in diffuse type of gastric cancer while WNT4 mRNA was found to be down-regulated in intestinal type of gastric cancer. Besides, CTGF gene overexpression was revealed in diffuse type of stomach cancer in comparison with that in intestinal type. Up-regulation of CTGF was also associated with lymph node metastasis., Conclusions: The findings show its expedient to perform further investigations in order to clarify diagnostic and prognostic value of CTGF, FGF12, and WNT4's in stomach cancer as well as the role of these genes in carcinogenesis.
- Published
- 2013
10. Intra-nuclear trafficking of the BLM helicase to DNA damage-induced foci is regulated by SUMO modification.
- Author
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Eladad S, Ye TZ, Hu P, Leversha M, Beresten S, Matunis MJ, and Ellis NA
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- Adenosine Triphosphatases genetics, DNA Damage physiology, DNA Helicases genetics, Fluorescent Antibody Technique, Humans, Leukemia, Promyelocytic, Acute metabolism, Mutation, Protein Structure, Tertiary, Protein Transport physiology, RecQ Helicases, Adenosine Triphosphatases metabolism, Cell Nucleus metabolism, DNA metabolism, DNA Helicases metabolism, SUMO-1 Protein metabolism
- Abstract
The Bloom syndrome gene, BLM, encodes a RecQ DNA helicase that when absent from the cell results in genomic instability and cancer predisposition. We show here that BLM is a substrate for small ubiquitin-like modifier (SUMO) modification, with lysines at K317, K331, K334 and K347 being preferred sites of modification. Unlike normal BLM, a double mutant BLM protein with lysine to arginine substitutions at residues 317 and 331 was not modified by SUMO, and it failed to localize efficiently to the PML nuclear bodies. Rather, double mutant BLM protein induced the formation of DNA damage-induced foci (DDI) that contained BRCA1 protein and phosphorylated histone H2AX. Double mutant BLM only partially complemented the genomic instability phenotypes of Bloom syndrome cells as assessed by sister-chromatid exchange and micronuclei formation assays. These results constitute evidence that BLM is a DNA damage sensor that signals the formation of DDI, and they establish SUMO modification as a negative regulator of BLM's signaling function.
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- 2005
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11. Functional link between BLM defective in Bloom's syndrome and the ataxia-telangiectasia-mutated protein, ATM.
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Beamish H, Kedar P, Kaneko H, Chen P, Fukao T, Peng C, Beresten S, Gueven N, Purdie D, Lees-Miller S, Ellis N, Kondo N, and Lavin MF
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- Adenosine Triphosphatases chemistry, Ataxia Telangiectasia Mutated Proteins, Cell Cycle Proteins, Cell Survival radiation effects, DNA Helicases chemistry, DNA-Binding Proteins, Humans, Mitosis, Phosphorylation, Precipitin Tests, Protein Serine-Threonine Kinases chemistry, Radiation Tolerance, RecQ Helicases, Sister Chromatid Exchange, Tumor Suppressor Proteins, Adenosine Triphosphatases physiology, Ataxia Telangiectasia genetics, Bloom Syndrome genetics, DNA Helicases physiology, Protein Serine-Threonine Kinases physiology
- Abstract
Chromosome aberrations, genomic instability, and cancer predisposition are hallmarks of a number of syndromes in which the defective genes recognize and/or repair DNA damage or are involved in some aspect of DNA processing. We report here direct interaction between BLM, mutated in Bloom's Syndrome (BS), and ATM, mutated is ataxia-telangiectasia, and we have mapped the sites of interaction. Full-length BLM cDNA corrected sister chromatid exchange (SCE) and radiosensitivity in BS cells. Mitotic phosphorylation of BLM was partially dependent on ATM, and phosphorylation sites on BLM were identified. A phosphospecific antibody against one of these sites (Thr-99) revealed radiation-induced phosphorylation, which was defective in ataxia-telangiectasia cells. Stable cell lines expressing phosphorylation site mutants failed to correct radiosensitivity in BS cells but corrected SCE. These mutants also sensitized normal control cells to radiation and increased radiation-induced chromosome aberrations but did not cause SCE numbers to increase. These data suggest that ATM and BLM function together in recognizing abnormal DNA structures by direct interaction and that these phosphorylation sites in BLM are important for radiosensitivity status but not for SCE frequency.
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- 2002
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12. Functional interaction of p53 and BLM DNA helicase in apoptosis.
- Author
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Wang XW, Tseng A, Ellis NA, Spillare EA, Linke SP, Robles AI, Seker H, Yang Q, Hu P, Beresten S, Bemmels NA, Garfield S, and Harris CC
- Subjects
- Apoptosis radiation effects, Binding Sites, Bloom Syndrome genetics, Cell Line, Cell Nucleus physiology, Cell Survival, Dose-Response Relationship, Radiation, Fibroblasts cytology, Fibroblasts physiology, Fibroblasts radiation effects, Fluorescent Antibody Technique, Indirect, Gamma Rays, Genes, Reporter, Humans, RecQ Helicases, Recombinant Proteins metabolism, Reference Values, Transfection, Adenosine Triphosphatases chemistry, Adenosine Triphosphatases metabolism, Apoptosis physiology, Bloom Syndrome enzymology, Cell Cycle physiology, DNA Damage, DNA Helicases chemistry, DNA Helicases metabolism, Tumor Suppressor Protein p53 chemistry, Tumor Suppressor Protein p53 metabolism
- Abstract
The Bloom syndrome (BS) protein, BLM, is a member of the RecQ DNA helicase family that also includes the Werner syndrome protein, WRN. Inherited mutations in these proteins are associated with cancer predisposition of these patients. We recently discovered that cells from Werner syndrome patients displayed a deficiency in p53-mediated apoptosis and WRN binds to p53. Here, we report that analogous to WRN, BLM also binds to p53 in vivo and in vitro, and the C-terminal domain of p53 is responsible for the interaction. p53-mediated apoptosis is defective in BS fibroblasts and can be rescued by expression of the normal BLM gene. Moreover, lymphoblastoid cell lines (LCLs) derived from BS donors are resistant to both gamma-radiation and doxorubicin-induced cell killing, and sensitivity can be restored by the stable expression of normal BLM. In contrast, BS cells have a normal Fas-mediated apoptosis, and in response to DNA damage normal accumulation of p53, normal induction of p53 responsive genes, and normal G(1)-S and G(2)-M cell cycle arrest. BLM localizes to nuclear foci referred to as PML nuclear bodies (NBs). Cells from Li-Fraumeni syndrome patients carrying p53 germline mutations and LCLs lacking a functional p53 have a decreased accumulation of BLM in NBs, whereas isogenic lines with functional p53 exhibit normal accumulation. Certain BLM mutants (C1055S or Delta133-237) that have a reduced ability to localize to the NBs when expressed in normal cells can impair the localization of wild type BLM to NBs and block p53-mediated apoptosis, suggesting a dominant-negative effect. Taken together, our results indicate both a novel mechanism of p53 function by which p53 mediates nuclear trafficking of BLM to NBs and the cooperation of p53 and BLM to induce apoptosis.
- Published
- 2001
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13. Evidence for BLM and Topoisomerase IIIalpha interaction in genomic stability.
- Author
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Hu P, Beresten SF, van Brabant AJ, Ye TZ, Pandolfi PP, Johnson FB, Guarente L, and Ellis NA
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- Adenosine Triphosphatases chemistry, Adenosine Triphosphatases genetics, Binding Sites, Bloom Syndrome metabolism, Cell Line, Transformed, DNA Helicases chemistry, DNA Helicases genetics, DNA Topoisomerases, Type I genetics, Gene Expression Regulation, HeLa Cells, Humans, Phenotype, Protein Structure, Tertiary, RecQ Helicases, Sister Chromatid Exchange, Tumor Cells, Cultured, Adenosine Triphosphatases metabolism, Bloom Syndrome enzymology, Bloom Syndrome genetics, DNA Helicases metabolism, DNA Topoisomerases, Type I metabolism
- Abstract
The genomic instability of persons with Bloom's syndrome (BS) features particularly an increased number of sister-chromatid exchanges (SCEs). The primary cause of the genomic instability is mutation at BLM, which encodes a DNA helicase of the RecQ family. BLM interacts with Topoisomerase IIIalpha (Topo IIIalpha), and both BLM and Topo IIIalpha localize to the nuclear organelles referred to as the promyelocytic leukemia protein (PML) nuclear bodies. In this study we show, by analysis of cells that express various deletion constructs of green fluorescent protein (GFP)-tagged BLM, that the first 133 amino acids of BLM are necessary and sufficient for interaction between Topo IIIalpha and BLM. The Topo IIIalpha-interaction domain of BLM is not required for BLM's localization to the PML nuclear bodies; in contrast, Topo IIIalpha is recruited to the PML nuclear bodies via its interaction with BLM. Expression of a full-length BLM (amino acids 1-1417) in BS cells can correct their high SCEs to normal levels, whereas expression of a BLM fragment that lacks the Topo IIIalpha interaction domain (amino acids 133-1417) results in intermediate SCE levels. The deficiency of amino acids 133-1417 in the reduction of SCEs was not explained by a defect in DNA helicase activity, because immunoprecipitated 133-1417 protein had 4-fold higher activity than GFP-BLM. The data implicate the BLM-Topo IIIalpha complex in the regulation of recombination in somatic cells.
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- 2001
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14. Regulation and localization of the Bloom syndrome protein in response to DNA damage.
- Author
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Bischof O, Kim SH, Irving J, Beresten S, Ellis NA, and Campisi J
- Subjects
- Adenosine Triphosphatases genetics, Bloom Syndrome genetics, Blotting, Western, Cell Fractionation, Cells, Cultured, DNA Helicases genetics, DNA Repair physiology, DNA-Binding Proteins metabolism, Fibroblasts metabolism, Fibroblasts radiation effects, Flow Cytometry, Humans, Microscopy, Fluorescence, Neoplasm Proteins metabolism, Nuclear Proteins genetics, Promyelocytic Leukemia Protein, Proteins metabolism, Rad51 Recombinase, RecQ Helicases, Replication Protein A, Transcription Factors metabolism, Tubulin metabolism, Tumor Suppressor Proteins, X-Rays, Adenosine Triphosphatases metabolism, Cell Cycle physiology, Cell Nucleus metabolism, DNA Damage, DNA Helicases metabolism, Nuclear Proteins metabolism
- Abstract
Bloom syndrome (BS) is an autosomal recessive disorder characterized by a high incidence of cancer and genomic instability. BLM, the protein defective in BS, is a RecQ-like helicase, presumed to function in DNA replication, recombination, or repair. BLM localizes to promyelocytic leukemia protein (PML) nuclear bodies and is expressed during late S and G2. We show, in normal human cells, that the recombination/repair proteins hRAD51 and replication protein (RP)-A assembled with BLM into a fraction of PML bodies during late S/G2. Biochemical experiments suggested that BLM resides in a nuclear matrix-bound complex in which association with hRAD51 may be direct. DNA-damaging agents that cause double strand breaks and a G2 delay induced BLM by a p53- and ataxia-telangiectasia mutated independent mechanism. This induction depended on the G2 delay, because it failed to occur when G2 was prevented or bypassed. It coincided with the appearance of foci containing BLM, PML, hRAD51 and RP-A, which resembled ionizing radiation-induced foci. After radiation, foci containing BLM and PML formed at sites of single-stranded DNA and presumptive repair in normal cells, but not in cells with defective PML. Our findings suggest that BLM is part of a dynamic nuclear matrix-based complex that requires PML and functions during G2 in undamaged cells and recombinational repair after DNA damage.
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- 2001
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15. Thermotolerant desert lizards characteristically differ in terms of heat-shock system regulation.
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Zatsepina OG, Ulmasov KA, Beresten SF, Molodtsov VB, Rybtsov SA, and Evgen'ev MB
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- Animals, DNA-Binding Proteins physiology, HSP70 Heat-Shock Proteins genetics, HSP70 Heat-Shock Proteins metabolism, Heat Shock Transcription Factors, Promoter Regions, Genetic, RNA, Messenger metabolism, Species Specificity, Transcription Factors, Desert Climate, Gene Expression Regulation, Heat-Shock Proteins genetics, Heat-Shock Proteins metabolism, Hot Temperature, Lizards physiology
- Abstract
We compare the properties and activation of heat-shock transcription factor (HSF1) and the synthesis of a major family of heat-shock proteins (HSP70) in lizard species inhabiting ecological niches with strikingly different thermal parameters. Under normal non-heat-shock conditions, all desert-dwelling lizard species studied so far differ from a northern, non-desert species (Lacerta vivipara) in the electrophoretic mobility and content of proteins constitutively bound to the regulatory heat-shock elements in the heat-shock gene promoter. Under these conditions, levels of activated HSF1 and of both HSP70 mRNA and protein are higher in the desert species than in the non-desert species. Upon heat shock, HSF1 aggregates in all species studied, although in desert species HSF1 subsequently disaggregates more rapidly. Cells of the northern species have a lower thermal threshold for HSP expression than those of the desert species, which correlates with the relatively low constitutive level of HSPs and high basal content of HSF1 in their cells.
- Published
- 2000
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16. Random-splitting of tRNA transcripts as an approach for studying tRNA-protein interactions.
- Author
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Aphasizhev R, Beresten S, Pugachev V, and Kisselev L
- Subjects
- Acylation, Animals, Base Sequence, Cattle, Electrophoresis, Polyacrylamide Gel, Kinetics, Molecular Sequence Data, Nucleic Acid Conformation, RNA, Transfer, Trp chemistry, Tryptophan-tRNA Ligase metabolism, Proteins metabolism, RNA, Transfer, Trp metabolism
- Abstract
Location of phosphodiester bonds essential for aminoacylation of bovine tRNA(Trp) was identified using a randomly cleaved transcript synthesized in vitro. It was found that cleavage of phosphodiester bonds after nucleotides in positions 21, 22, 36-38, 57-59, 62 and 64 were critical for aminoacylation capacity of tRNA(Trp)-transcript. These cleavage sites were located in the regions of tRNA molecule protected by the cognate synthetase against chemical modification and in the regions presumably outside the contact area as well. These results indicate that for maintenance of aminoacylation ability the intactness of the certain regions of the tRNA backbone structure is necessary. Random splitting of non-modified RNA with alkali followed by separation of active and inactive molecules and identification of cleavage sites developed in this work may become a general approach for studying the role of RNA covalent structure in its interaction with proteins.
- Published
- 1993
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17. Aminoacyl-tRNA synthetase-induced cleavage of tRNA.
- Author
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Beresten S, Jahn M, and Söll D
- Subjects
- Base Sequence, Escherichia coli genetics, Escherichia coli metabolism, Kinetics, Magnesium metabolism, Molecular Sequence Data, Mutation genetics, Nucleic Acid Conformation, RNA, Transfer, Gln chemistry, RNA, Transfer, Trp chemistry, RNA, Transfer, Trp metabolism, Amino Acyl-tRNA Synthetases metabolism, Escherichia coli enzymology, RNA, Transfer, Gln metabolism
- Abstract
Aminoacyl-tRNA synthetases interact with their cognate tRNAs in a highly specific fashion. We have examined the phenomenon that upon complex formation E. coli glutaminyl-tRNA synthetase destabilizes tRNA(Gln) causing chain scissions in the presence of Mg2+ ions. The phosphodiester bond cleavage produces 3'-phosphate and 5'-hydroxyl ends. This kind of experiment is useful for detecting conformational changes in tRNA. Our results show that the cleavage is synthetase-specific, that mutant and wild-type tRNA(Gln) species can assume a different conformation, and that modified nucleosides in tRNA enhance the structural stability of the molecule.
- Published
- 1992
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18. Immuno-chemical non-cross-reactivity between eukaryotic and prokaryotic seryl-tRNA synthetases.
- Author
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Sidorik LL, Gudzera OI, Dragovoz VA, Tukalo MA, and Beresten SF
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- Animals, Antibodies, Blotting, Western, Cattle, Cross Reactions, Enzyme-Linked Immunosorbent Assay, Escherichia coli enzymology, Immunohistochemistry, Liver enzymology, Rabbits, Serine-tRNA Ligase immunology, Serine-tRNA Ligase metabolism
- Abstract
Monospecific polyclonal antibodies (pAbs) against highly purified bovine seryl-tRNA synthetase (SerRS, EC 6.1.1.1) were prepared and their specificity tested. The interactions of pAbs with SerRS from different organisms were investigated by protein immunoblotting and ELISA methods. pAbs inhibit eukaryotic SerRS aminoacylating activity and exert no effect on SerRS activity from prokaryotes. It is proposed that prokaryotic and eukaryotic SerRS evolve from different ancestor genes.
- Published
- 1991
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19. Mutual conformational changes of tryptophanyl-tRNA synthetase and tRNATrp in the course of their specific interaction.
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Beresten S, Scheinker V, Favorova O, and Kisselev L
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- Animals, Autoradiography, Cattle, Chemical Phenomena, Chemistry, Circular Dichroism, Hydrolysis, Molecular Conformation, Pancreas enzymology, Protein Binding, Saccharomyces cerevisiae metabolism, Trypsin, Amino Acyl-tRNA Synthetases metabolism, RNA, Transfer, Amino Acyl metabolism, Tryptophan-tRNA Ligase metabolism
- Abstract
tRNATrp (beef, yeast) is capable of accelerating limited tryptic hydrolysis of the N-terminal part in the polypeptide chains of dimeric beef pancreas tryptophanyl-tRNA synthetase; it can also eliminate the protective effect of tryptophanyl adenylate on the enzyme proteolysis. The effect of tRNA on the proteolysis is manifested even when the 3'-CCA terminus is removed. It has been concluded that the conformation of the synthetase changes when it forms a complex with tRNATrp. Yeast tRNATrp lacking the 3'-half of the acceptor stem can still interact with the synthetase and, to certain extent, induces changes in the conformation of the latter. The susceptibility of single-stranded and double-stranded regions of tRNATrp to cleavage with endonucleases has been studied, and the results are indicative of the fact that, regardless of considerable differences in the nucleotide sequence of yeast and beef tRNATrp, their three-dimensional structures are similar. This fact is consistent with the finding that parameters for the interaction of these tRNAsTrp with beef tryptophanyl-tRNA synthetase are rather close. The three-dimensional structure of tRNATrp is altered when the enzyme forms a complex with it, as seen from (a) a change in the circular dichroic spectrum and (b) an elevated susceptibility of the anticodon and, apparently, acceptor stems to cleavage with nuclease. The conversion of exposed cytidine residues in tRNATrp into uridine residues results in a loss of the acceptor activity; the capability to accelerate limited tryptic hydrolysis of tryptophanyl-tRNA synthetase is also lost although the enzyme-substrate complex, as seen from circular dichroic spectra, can still be formed. The conversion of cytosine in the anticodon stem into uracil modifies the conformation of the anticodon stem. The anticodon arm (including the anticodon) and the acceptor stem play an essential role in the interaction between tRNATrp and tryptophanyl-tRNA synthetase.
- Published
- 1983
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20. Immunochemical studies of beef pancreas tryptophanyl-tRNA synthetase and its fragments. Determination of the number of antigenic determinants and a comparison with tryptophanyl- tRNA synthetases from other sources and with reverse transcriptase from avian myeloblastosis virus.
- Author
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Scheinker VS, Beresten SF, Mazo AM, Ambartsumyan NS, Rokhlin OV, Favorova OO, and Kisselev LL
- Subjects
- Animals, Cattle, Chickens, Immunoglobulin Fab Fragments, Liver enzymology, Molecular Weight, Peptide Fragments, Radioimmunoassay, Rats, Species Specificity, Swine, Trypsin, Amino Acyl-tRNA Synthetases immunology, Avian Leukosis Virus enzymology, Avian Myeloblastosis Virus enzymology, Epitopes, Immunoglobulin G, Pancreas enzymology, RNA-Directed DNA Polymerase immunology, Tryptophan-tRNA Ligase immunology
- Abstract
The immunoglobulin G (IgG) fraction of the antiserum from rabbits immunized with homogeneous beef pancreas tryptophanyl-tRNA synthetase inhibits the enzyme activity in the reactions of both tRNATrp aminoacylation and tryptophan activation. Fab fragments of IgG act in a similar way. Common antigenic determinants have been detected in tryptophanyl-tRNA synthetases from beef, pig, chicken and rat livers using pure antibodies against beef pancreas tryptophanyl-tRNA synthetase. This observation indicates the evolutional stability of certain structural features of tryptophanyl-tRNA synthetases. The interaction of antibodies with the fragments of beef tryptophanyl-tRNA synthetase produced by endogenous and tryptic proteolysis of the enzyme has been studied. On third of the antiserum antibodies interacting with the C-terminal fragment of the enzyme (Mr approximately equal to 40000) inhibits its activity whereas the antibodies to the N-terminal fragment (Mr approximately equal to 20000) have no effect on the enzyme activity. The immunochemical identity of the two synthetase fragments differing in their enzymatic activity supports the assumption that the loss of enzymatic activity of the tryptic fragment is caused by lack of a small peptide which is retained in case of endogenous proteolysis; probably the amino acid residues of this peptide participate in formation of active centre of tryptophanyl-tRNA synthetase. A radioimmunochemical method is described for determining the number of antigenic determinants. One molecule of tryptophanyl-tRNA synthetase was found to bind 9 (+/- 1) molecules of Fab fragments. Antibodies against tryptophanyl-tRNA snythetase from beef pancreas do not inhibit noticeably the activity of reverse transcriptase from avian myeloblastosis virus. No antigenic determinants in common have been detected in reverse transcriptase and tryptophanyl-tRNA synthetase by radioimmunochemical assays.
- Published
- 1979
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21. Molecular and cellular studies of tryptophanyl-tRNA synthetase using monoclonal antibodies. Evaluation of a common antigenic determinant in eukaryotic, prokaryotic and archaebacterial enzymes which maps outside the catalytic domain.
- Author
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Beresten SF, Zargarova TA, Favorova OO, Rubikaite BI, Ryazanov AG, and Kisselev LL
- Subjects
- Animals, Biological Evolution, Cattle, Escherichia coli enzymology, Mice, Mice, Inbred BALB C, Peptide Mapping, Tryptophan-tRNA Ligase analysis, Tryptophan-tRNA Ligase isolation & purification, Amino Acyl-tRNA Synthetases immunology, Antibodies, Monoclonal, Archaea enzymology, Bacteria enzymology, Epitopes analysis, Tryptophan-tRNA Ligase immunology
- Abstract
Monoclonal antibodies referred to as Am1, Am2 and Am3 against highly purified bovine tryptophanyl-tRNA synthetase were prepared. Am2 antibodies inhibit the Trp-tRNA synthetase activity and interact with the active truncated enzyme forms (dimers of either 40-kDa or 51-kDa fragments) produced by limited proteolysis. Am1 and Am3 antibodies exert no effect on the Trp-tRNA synthetase activity; epitopes recognized by them are mapped close to one another and reside at the dispensable part of the Trp-tRNA synthetase molecule. Am1 cross-reacts with Trp-tRNA synthetases of eukaryotic, prokaryotic and archaebacterial species, as revealed by immunoblot analysis. A rapid two-step technique was developed for isolating electrophoretically homogeneous Trp-tRNA synthetase from Escherichia coli. The purified enzyme interacted with Am1, but not with Am2 and Am3 antibodies taken at the same concentrations. As in the case of eukaryotic Trp-tRNA synthetase, Am1 did not influence the activity of Trp-tRNA synthetase from E. coli. From the aforementioned results it follows that: (a) the conservation of part of the Trp-tRNA synthetase structure which is not directly involved in the formation of the catalytic centre of prokaryotic and eukaryotic Trp-tRNA synthetases suggests that the dispensable part of the molecule might be involved in some additional biological function(s) of Trp-tRNA synthetase besides tRNA(Trp) charging; (b) the common antigenic determinant in Trp-tRNA synthetase of eukaryotes, prokaryotes and archaebacteria indicates that this enzyme was presumably present in the common ancestor of the above organisms.
- Published
- 1989
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22. Role of exposed cytosine residues in aminoacylation activity of tRNATrp.
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Scheinker VS, Beresten SF, Mashkova TD, Mazo AM, and Kisselev LL
- Subjects
- Animals, Anticodon metabolism, Base Sequence drug effects, Cattle, Nucleic Acid Conformation drug effects, Structure-Activity Relationship, Sulfites pharmacology, Tryptophan metabolism, Tryptophan-tRNA Ligase metabolism, Uridine metabolism, Cytosine metabolism, RNA, Transfer, Amino Acyl metabolism
- Published
- 1981
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23. Negative cooperativity in adenylate formation catalysed by beef pancreas tryptophanyl-tRNA synthetase: influence of tRNATrp.
- Author
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Degtyarev SK, Beresten SF, Denisov AYu, Lavrik OI, and Kisselev LL
- Subjects
- Animals, Cattle, Kinetics, Spectrometry, Fluorescence, Tryptophan, Adenosine Monophosphate metabolism, Amino Acyl-tRNA Synthetases metabolism, Pancreas enzymology, RNA, Transfer, Amino Acyl pharmacology, Tryptophan-tRNA Ligase metabolism
- Published
- 1982
- Full Text
- View/download PDF
24. The effect of tRNA and tryptophanyl adenylate on limited proteolysis of beef pancreas tryptophanyl-tRNA synthetase.
- Author
-
Scheinker VS, Beresten SF, Degtyarev SK, and Kisselev LL
- Subjects
- Animals, Cattle, Kinetics, Molecular Weight, Protein Binding, Adenosine Monophosphate analogs & derivatives, Amino Acyl-tRNA Synthetases, Pancreas enzymology, RNA, Transfer, Trypsin, Tryptophan analogs & derivatives, Tryptophan-tRNA Ligase
- Abstract
Limited proteolysis of tryptophanyl-tRNA synthetase was used to detect changes in the enzyme molecule in the presence of substrates. Trypsinolysis of each of the two identical subunits occurs in succession from the N-terminus as follows: 60 leads to 51 leads to 40 leads to 24 kilodaltons. The transition 51 leads to 40 is hindered in tryptophanyl adenylate.enzyme complex. Yeast tRNATrp accelerates the first steps of hydrolysis and decelerates the transition 40 leads to 24. Once tRNATrp is added to the synthetase.adenylate complex, the protective effect of the adenylate disappears. The same effects are found also in the presence of tRNATrp oxidized with NaI04 and tRNATrp lacking the 3'-terminal adenosine. Oxidized tRNATrp (but not tRNATrp without the 3'-A) accelerates tryptophan-dependent hydrolysis of ATP catalyzed by the enzyme. A scheme is proposed for the interaction of yeast tRNATrp with beef pancreas tryptophanyl-tRNA synthetase involving the association of tRNA with a positively charged site(s) of the enzyme and the changes in the conformation of enzyme manifesting itself in unfolding of the acidic N-terminal fragment of the polypeptide chain and in the exposure of the adenylate.
- Published
- 1979
- Full Text
- View/download PDF
25. Molecular and cellular studies of tryptophanyl-tRNA synthetases using monoclonal antibodies. Remarkable variations in the content of tryptophanyl-tRNA synthetase in the pancreas of different mammals.
- Author
-
Favorova OO, Zargarova TA, Rukosuyev VS, Beresten SF, and Kisselev LL
- Subjects
- Animals, Cattle, Humans, Immunoblotting, Liver enzymology, Rabbits, Rats, Sheep, Species Specificity, Swine, Tryptophan-tRNA Ligase physiology, Amino Acyl-tRNA Synthetases analysis, Antibodies, Monoclonal, Pancreas enzymology, Tryptophan-tRNA Ligase analysis
- Abstract
The content of Trp-tRNA synthetase in pancreas and liver of cattle, sheep, swine, rat, rabbit and man was assayed by direct radioimmunoblotting with a 125I-labelled monoclonal antibody Am1, specifically interacting with any eukaryotic Trp-tRNA synthetase. Its content in the organs studied, with the exception of bovine and sheep pancreas, was found to be 0.002-0.012% of total proteins. The enzyme content in bovine pancreas was about 0.2% of total proteins, i.e. 70 times higher than in bovine liver; similar correlations were found for sheep. The Trp-tRNA synthetase levels in each organ varied from animal to animal of the same species by not more than a factor of four; these individual variations cannot affect the conclusion about the profound differences in the levels of the enzyme in pancreases of Ruminantia and of the other mammalians. As shown by indirect immunofluorescence technique, bovine Trp-tRNA synthetase is mainly located in the exocrine part of the pancreas. Moreover, the immunoreactive material is detectable also in bovine (not human) pancreatic juice. The abnormally high Trp-tRNA synthetase content in the ruminant pancreas may be connected with unknown function(s) of this protein somehow related to the peculiarities of digestion of these mammals.
- Published
- 1989
- Full Text
- View/download PDF
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