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Arkhipov VI Kulagina TP Shevchenko NA 《Zhurnal vysshe? nervno? deiatelnosti imeni I P Pavlova》2004,54(2):202-209
Learning and memory disorders accompanying epileptogenesis were studied in rats with the use of two experimental models of epilepsy, picrotoxin kindling and kainic treatment. Rise of exploratory activity and decrease in animal's capability for experimental extinction of a response were characteristic of the initial stage of epileptogenesis. It was suggested that a dysfunction of brain hippocampal system can be responsible for cognitive disorders. To reveal their mechanisms, lipid contents were determined in the neocortex and hippocampus in appropriate periods after exposure to epileptogenic factors. Long-term changes in hippocampal lipid spectrum were found five days after the exposure to kainic acid. In particular, after sodium valproate treatment (the compensation of kainic effects), the total content of phospholipids in hippocampus was decreased. The hippocampal sphingomyelin level dropped as a result of picrotoxin kindling. The sphingomyelin changes suggest some recovery processes in hippocampal cells and point to an adaptive role of membrane lipids in the mechanisms of the damaging epiptogenous effects. 相似文献
34.
The synthesis of the new radioprotective compounds ATB (I, 2-allylthioureidobenzoic acid), PTB (II, 2-phenylthioureidobenzoic acid), A-2-PTU (III, N-allyl-N"-2-pyridylthiourea), and P-2-PTU (IV, N-phenyl-N"-2-pyridylthiourea) and their influence on biological and genetic effects of gamma rays was studied. In result of investigations it must be noted that PTB displayed radioprotective effect as a result of which more plants in M1 germination and survive in M2 of the induced mutations is increased. The cytological analysis reveals that the studied substance (PTB) decreases chromosome aberration in meristem cells of pea roots almost twice as a result of postirradiation treatment. The effect of A-2-PTU in the experiments with peas greatly depends on the dose of irradiation, i.e., on the degree of damaging of the processes of cell restoration and the possibility of their partial restoration after the treatment with the protector. The results obtained suggest that chemical compounds of N,N"-disubstituted thiourea group (A-2-PTU and P-2-PTU) exert strong radioprotective effect in the experiments with peas. This is of great importance to modern radiobiology and radiation mutagenesis and also to protect hereditary structures against radiation. 相似文献
35.
Roguev A Schaft D Shevchenko A Aasland R Shevchenko A Stewart AF 《The Journal of biological chemistry》2003,278(10):8487-8493
Histone 3 lysine 4 (H3 Lys(4)) methylation in Saccharomyces cerevisiae is mediated by the Set1 complex (Set1C) and is dependent upon ubiquitinylation of H2B by Rad6. Mutually exclusive methylation of H3 at Lys(4) or Lys(9) is central to chromatin regulation; however, S. cerevisiae lacks Lys(9) methylation. Furthermore, a different H3 Lys(4) methylase, Set 7/9, has been identified in mammals, thereby questioning the relevance of the S. cerevisiae findings for eukaryotes in general. We report that the majority of Lys(4) methylation in Schizosaccharomyces pombe, like in S. cerevisiae, is mediated by Set1C and is Rad6-dependent. S. pombe Set1C mediates H3 Lys(4) methylation in vitro and contains the same eight subunits found in S. cerevisiae, including the homologue of the Drosophila trithorax Group protein, Ash2. Three additional features of S. pombe Set1C each involve PHD fingers. Notably, the Spp1 subunit is dispensable for H3 Lys(4) methylation in budding yeast but required in fission yeast, and Sp_Set1C has a novel proteomic hyperlink to a new complex that includes the homologue of another trithorax Group protein, Lid (little imaginal discs). Thus, we infer that Set1C is highly conserved in eukaryotes but observe that its links to the proteome are not. 相似文献
36.
Shevchenko VP Nagaev IIu Miasoedov NF Kamernitskiĭ AV Levina IS Kulikova LE 《Bioorganicheskaia khimiia》2002,28(3):258-260
6-O-(3-Methoxycarbonylpropyl)- and 6-O-(3-carboxypropyl)oximes of 16 alpha,17 alpha-cyclohexanopregn-4-ene-3,6,20-trione labeled by tritium in position 1,2 were synthesized. When using homogenous catalysts, the molar radioactivity of the resulting preparations was 1.5-1.7 PBq/mol. 相似文献
37.
Analysis of the adenovirus E1B-55K-anchored proteome reveals its link to ubiquitination machinery 总被引:7,自引:0,他引:7 下载免费PDF全文
During the early phase of infection, the E1B-55K protein of adenovirus type 5 (Ad5) counters the E1A-induced stabilization of p53, whereas in the late phase, E1B-55K modulates the preferential nucleocytoplasmic transport and translation of the late viral mRNAs. The mechanism(s) by which E1B-55K performs these functions has not yet been clearly elucidated. In this study, we have taken a proteomics-based approach to identify and characterize novel E1B-55K-associated proteins. A multiprotein E1B-55K-containing complex was immunopurified from Ad5-infected HeLa cells and found to contain E4-orf6, as well as several cellular factors previously implicated in the ubiquitin-proteasome-mediated destruction of proteins, including Cullin-5, Rbx1/ROC1/Hrt1, and Elongins B and C. We further demonstrate that a complex containing these as well as other proteins is capable of directing the polyubiquitination of p53 in vitro. These ubiquitin ligase components were found in a high-molecular-mass complex of 800 to 900 kDa. We propose that these newly identified binding partners (Cullin-5, Elongins B and C, and Rbx1) complex with E1B-55K and E4-orf6 during Ad infection to form part of an E3 ubiquitin ligase that targets specific protein substrates for degradation. We further suggest that E1B-55K functions as the principal substrate recognition component of this SCF-type ubiquitin ligase, whereas E4-orf6 may serve to nucleate the assembly of the complex. Lastly, we describe the identification and characterization of two novel E1B-55K interacting factors, importin-alpha 1 and pp32, that may also participate in the functions previously ascribed to E1B-55K and E4-orf6. 相似文献
38.
Shevchenko A Schaft D Roguev A Pijnappel WW Stewart AF Shevchenko A 《Molecular & cellular proteomics : MCP》2002,1(3):204-212
We employed a combination of tandem affinity purification and mass spectrometry for deciphering protein complexes and the protein interaction network in budding yeast. 53 genes were epitope-tagged, and their interaction partners were isolated by two-step immunoaffinity chromatography from whole cell lysates. 38 baits pulled down a total of 220 interaction partners, which are members of 19 functionally distinct protein complexes. We identified four proteins shared between complexes of different functionality thus charting segments of a protein interaction network. Concordance with the results of genome-wide two-hybrid screening was poor (14% of identified interactors overlapped) suggesting that the two approaches may provide complementary views on physical interactions within the proteome. 相似文献
39.
Miazin AE Osipov AN Elakov AL Sypin VD Shevchenko VA 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2002,42(6):731-734
The single-strand DNA level in spleen lymphocytes of BALB/c male-mice after 11 month acute exposure to gamma-radiation at doses 1, 3 and 6 Gy has been investigated by comet assay. The results of our study showed that at 11 month after irradiation at different doses a significant increase in the level of DNA breaks in spleen lymphocytes and decrease in the total number of these cells in mice was registered. It is possible that the increase in the DNA breaks is due to the effort of the compensatory proliferation process in lymphoid system that can give the increase in the number of different genetic disturbances in lymphocytes. 相似文献
40.
Mirzoev EB Kobialko VO Konopleva IV Shevchenko TS Gubina OA Verkhovskiĭ IuG 《Radiatsionnaia biologiia, radioecologiia / Rossi?skaia akademiia nauk》2002,42(3):274-278
Chronic irradiation of sheep with doses of 2.6 and 12.9 mC.kg was characterized by the modification of the adenylatecyclase activity and Ca2+ permeability of plasma membrane in cells of the peripheric blood, with no changes in the clinical and hematological indicators. The observed effects are assumed to result from structural and dynamic variations in the lipids of membranes. 相似文献