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Jakovljevic Biljana Nikolic Turnic Tamara Jeremic Nevena Jeremic Jovana Bradic Jovana Ravic Marko Jakovljevic Vladimir Lj. Jelic Djordje Radovanovic Dragan Pechanova Olga Zivkovic Vladimir 《Molecular and cellular biochemistry》2019,453(1-2):111-119
Molecular and Cellular Biochemistry - Melatonin is a crucial neurohormone synthesized in the pineal gland that influences the physiology of animals. The molecular mechanism of norepinephrine... 相似文献
3.
A covalently bound photoisomerizable agonist. Comparison with reversibly bound agonists at electrophorus electroplaques 下载免费PDF全文
HA Lester ME Krouse MM Nass NH Wassermann BF Erlanger 《The Journal of general physiology》1980,75(2):207-232
After disulphide bonds are reduced with dithiothreitol, trans-3- (α-bromomethyl)-3’-[α- (trimethylammonium)methyl]azobenzene (trans-QBr) alkylates a sulfhydryl group on receptors. The membrane conductance induced by this “tethered agonist” shares many properties with that induced by reversible agonists. Equilibrium conductance increases as the membrane potential is made more negative; the voltage sensitivity resembles that seen with 50 [mu]M carbachol. Voltage- jump relaxations follow an exponential time-course; the rate constants are about twice as large as those seen with 50 μM carbachol and have the same voltage and temperature sensitivity. With reversible agonists, the rate of channel opening increases with the frequency of agonist-receptor collisions: with tethered trans-Qbr, this rate depends only on intramolecular events. In comparison to the conductance induced by reversible agonists, the QBr-induced conductance is at least 10-fold less sensitive to competitive blockade by tubocurarine and roughly as sensitive to “open-channel blockade” bu QX-222. Light-flash experiments with tethered QBr resemble those with the reversible photoisomerizable agonist, 3,3’,bis-[α-(trimethylammonium)methyl]azobenzene (Bis-Q): the conductance is increased by cis {arrow} trans photoisomerizations and decreased by trans {arrow} cis photoisomerizations. As with Bis-Q, ligh-flash relaxations have the same rate constant as voltage-jump relaxations. Receptors with tethered trans isomer. By comparing the agonist-induced conductance with the cis/tans ratio, we conclude that each channel’s activation is determined by the configuration of a single tethered QBr molecule. The QBr-induced conductance shows slow decreases (time constant, several hundred milliseconds), which can be partially reversed by flashes. The similarities suggest that the same rate-limiting step governs the opening and closing of channels for both reversible and tethered agonists. Therefore, this step is probably not the initial encounter between agonist and receptor molecules. 相似文献
4.
Vesna Djikanovic Momir Paunovic Vera Nikolic Predrag Simonovic Predrag Cakic 《Reviews in Fish Biology and Fisheries》2012,22(1):297-324
As a result of freshwater fish parasitofauna investigations, throughout the past 75 years, the number of parasitic species
is presented. This paper reviews the history, current state, and tendencies of the fish parasitofauna studies in Serbian open
waters. Up to now, in total 170 parasitic species have been reported. Systematic parasitofauna investigations have been carried
out on 54 freshwater fish species in waters of the Danube River Basin in Serbia, also in hill-mountanious watercourses, lakes
and salmonid fishpond of Sjenicko-Pesterska plateau (south-west region of Serbia), Homolje area (east Serbia), and in Vlasina
lake (south-east Serbia). This data review pointed that it is necessary to continue the investigation on fish parasites in
Serbia. The data on freshwater fish parasites are important for evaluation of general influence on the community structure. 相似文献
5.
Background
A recent epidemiological study demonstrated a reduced risk of lung cancer mortality in breast cancer patients using antiestrogens. These and other data implicate a role for estrogens in lung cancer, particularly nonsmall cell lung cancer (NSCLC). Approximately 61% of human NSCLC tumors express nuclear estrogen receptor β (ERβ); however, the role of ERβ and estrogens in NSCLC is likely to be multifactorial. Here we tested the hypothesis that proteins interacting with ERβ in human lung adenocarcinoma cells that respond proliferatively to estradiol (E2) are distinct from those in non-E2-responsive cells.Methods
FLAG affinity purification of FLAG-ERβ-interacting proteins was used to isolate ERβ-interacting proteins in whole cell extracts from E2 proliferative H1793 and non-E2-proliferative A549 lung adenocarcinoma cell lines. Following trypsin digestion, proteins were identified using liquid chromatography electrospray ionization tandem mass spectrometry (LC-MS/MS). Proteomic data were analyzed using Ingenuity Pathway Analysis. Select results were confirmed by coimmunoprecipitation.Results
LC-MS/MS identified 27 non-redundant ERβ-interacting proteins. ERβ-interacting proteins included hsp70, hsp60, vimentin, histones and calmodulin. Ingenuity Pathway Analysis of the ERβ-interacting proteins revealed differences in molecular and functional networks between H1793 and A549 lung adenocarcinoma cells. Coimmunoprecipitation experiments in these and other lung adenocarcinoma cells confirmed that ERβ and EGFR interact in a gender-dependent manner and in response to E2 or EGF. BRCA1 interacted with ERβ in A549 cell lines and in human lung adenocarcinoma tumors, but not normal lung tissue.Conclusion
Our results identify specific differences in ERβ-interacting proteins in lung adenocarcinoma cells corresponding to ligand-dependent differences in estrogenic responses.6.
Annemarie MM Vlaar Angela EP Bouwmans Marinus JPG van Kroonenburgh Werner H Mess Selma C Tromp Piet GWM Wuisman Alfons GH Kessels Ania Winogrodzka Wim EJ Weber 《BMC neurology》2007,7(1):28
Background
Parkinson's disease (PD) is the second most common neurodegenerative disorder. As there is no definitive diagnostic test, its diagnosis is based on clinical criteria. Recently transcranial duplex scanning (TCD) of the substantia nigra in the brainstem has been proposed as an instrument to diagnose PD. We and others have found that TCD scanning of substantia nigra duplex is a relatively accurate diagnostic instrument in patients with parkinsonian symptoms. However, all studies on TCD so far have involved well-defined, later-stage PD patients, which will obviously lead to an overestimate of the diagnostic accuracy of TCD. 相似文献7.
The K homology-type splicing regulatory protein, KSRP, activates splicing through intronic splicing enhancer sequences. It is highly expressed in neural cells and is required for the neural-specific splicing of the c-src N1 exon. In this study, we mapped the gene (gene symbols KHSRP and Khsrp) to human chromosome 19 by using radiation hybrid panels and to mouse chromosome 17 by studying an interspecific backcross panel. Human KHSRP is a positional candidate gene for familial febrile convulsion and Cayman type cerebellar ataxia. Comparative analysis of the human and mouse genomes indicates that the KHSRP gene is located in regions of conserved synteny between the two species. 相似文献
8.
Lu X Nikolic D Mitchell DJ van Breemen RB Mersfelder JA Hille R Silverman RB 《Bioorganic & medicinal chemistry letters》2003,13(22):4129-4132
Experiments are described to determine the origin of the 6-hydroxyl group of 6-hydroxyFMN produced by the substrate-induced transformation of FMN in the C30A mutant of trimethylamine dehydrogenase. The conversion of FMN to 6-hydroxyFMN is carried out in the presence of H(2)(18)O and 18O(2), and the results clearly show that the 6-hydroxyl group is derived from molecular oxygen and not from water. 相似文献
9.
Cooperative assembly of an hnRNP complex induced by a tissue-specific homolog of polypyrimidine tract binding protein 总被引:13,自引:0,他引:13 下载免费PDF全文
Markovtsov V Nikolic JM Goldman JA Turck CW Chou MY Black DL 《Molecular and cellular biology》2000,20(20):7463-7479
Splicing of the c-src N1 exon in neuronal cells depends in part on an intronic cluster of RNA regulatory elements called the downstream control sequence (DCS). Using site-specific cross-linking, RNA gel shift, and DCS RNA affinity chromatography assays, we characterized the binding of several proteins to specific sites along the DCS RNA. Heterogeneous nuclear ribonucleoprotein (hnRNP) H, polypyrimidine tract binding protein (PTB), and KH-type splicing-regulatory protein (KSRP) each bind to distinct elements within this sequence. We also identified a new 60-kDa tissue-specific protein that binds to the CUCUCU splicing repressor element of the DCS RNA. This protein was purified, partially sequenced, and cloned. The new protein (neurally enriched homolog of PTB [nPTB]) is highly homologous to PTB. Unlike PTB, nPTB is enriched in the brain and in some neural cell lines. Although similar in sequence, nPTB and PTB show significant differences in their properties. nPTB binds more stably to the DCS RNA than PTB does but is a weaker repressor of splicing in vitro. nPTB also greatly enhances the binding of two other proteins, hnRNP H and KSRP, to the DCS RNA. These experiments identify specific cooperative interactions between the proteins that assemble onto an intricate splicing-regulatory sequence and show how this hnRNP assembly is altered in different cell types by incorporating different but highly related proteins. 相似文献
10.
BACKGROUND: The p35-Cdk5 kinase has been implicated in a variety of functions in the central nervous system (CNS), including axon outgrowth, axon guidance, fasciculation, and neuronal migration during cortical development. In p35(-/-) mice, embryonic cortical neurons are unable to migrate past their predecessors, leading to an inversion of cortical layers in the adult cortex. RESULTS: In order to identify molecules important for p35-Cdk5-dependent function in the cortex, we screened for p35-interacting proteins using the two-hybrid system. In this study, we report the identification of a novel interaction between p35 and the versatile cell adhesion signaling molecule beta-catenin. The p35 and beta-catenin proteins interacted in vitro and colocalized in transfected COS cells. In addition, the p35-Cdk5 kinase was associated with a beta-catenin-N-cadherin complex in the cortex. In N-cadherin-mediated aggregation assays, inhibition of Cdk5 kinase activity using the Cdk5 inhibitor roscovitine led to the formation of larger aggregates of embryonic cortical neurons. This finding was recapitulated in p35(-/-) cortical neurons, which aggregated to a greater degree than wild-type neurons. In addition, introduction of active p35-Cdk5 kinase into COS cells led to a decreased beta-catenin-N-cadherin interaction and loss of cell adhesion. CONCLUSIONS: The association between p35-Cdk5 and an N-cadherin adhesion complex in cortical neurons and the modulation of N-cadherin-mediated aggregation by p35-Cdk5 suggests that the p35-Cdk5 kinase is involved in the regulation of N-cadherin-mediated adhesion in cortical neurons. 相似文献