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1.
Acta Neurol Scand ; 133(5): 398-402, 2016 May.
Artigo em Inglês | MEDLINE | ID: mdl-26248690

RESUMO

BACKGROUND: Paraneoplastic neurological syndromes (PNS) are rare remote effect of cancer. The antibodies and tumors associated with PNS have been well described, but there are still many clinically suspected cases in which no tumor or antibody can be identified. This is the first report of PNS showing hot cross-bun sign and caused by exceptionally rare underlying malignancy, such as burned-out testicular tumor. CASE PRESENTATION: A 42-year-old man presented subacute progression of hearing loss and cerebellar ataxia. Cerebrospinal fluid showed continuous inflammation and magnetic resonance imaging (MRI) revealed cerebellar atrophy and hot cross-bun sign. Resection of tumors improved both laboratory findings and neurological signs and their pathology was seminoma. CONCLUSION: Seminoma can cause PNS showing 8th cranial nerve palsy, cerebellar, and brainstem atrophy with hot cross-bun sign on MRI study. Extensive screening for onconeural antibodies was negative and thereby suggested that unknown antibodies worked for both antitumor immunity and induction of PNS.


Assuntos
Síndromes Paraneoplásicas do Sistema Nervoso/diagnóstico , Seminoma/complicações , Neoplasias Testiculares/complicações , Adulto , Humanos , Masculino , Síndromes Paraneoplásicas do Sistema Nervoso/etiologia
3.
Neuron ; 14(6): 1189-99, 1995 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-7605632

RESUMO

Plexin (previously referred to as B2) is a neuronal cell surface molecule that has been identified in Xenopus. cDNA cloning reveals that plexin has no homology to known neuronal cell surface molecules but possesses, in its extracellular segment, three internal repeats of cysteine clusters that are homologous to the cysteine-rich domain of the c-met proto-oncogene protein product. The exogenous plexin proteins expressed on the surfaces of L cells by cDNA transfection mediate cell adhesion via a homophilic binding mechanism, under the presence of calcium ions. Plexin is expressed in the receptors and neurons of particular sensory systems. These findings indicate that plexin is a novel calcium-dependent cell adhesion molecule and suggest its involvement in specific neuronal cell interaction and/or contact.


Assuntos
Cálcio/farmacologia , Moléculas de Adesão Celular/metabolismo , Adesão Celular/fisiologia , Proteínas do Tecido Nervoso/metabolismo , Sequência de Aminoácidos , Animais , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/genética , Membrana Celular/metabolismo , Clonagem Molecular , DNA Complementar/química , DNA Complementar/genética , DNA Complementar/isolamento & purificação , Células L , Camundongos , Dados de Sequência Molecular , Proteínas do Tecido Nervoso/química , Proteínas do Tecido Nervoso/genética , Neurônios/metabolismo , Nariz/inervação , Bulbo Olfatório/metabolismo , Proteínas Proto-Oncogênicas c-met , Receptores Proteína Tirosina Quinases/química , Homologia de Sequência , Transfecção , Vestíbulo do Labirinto/metabolismo , Xenopus
4.
Neuron ; 12(1): 219-34, 1994 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-8292358

RESUMO

A consistent rat model for the study of the consequences of congophilic and fibrillar A beta-amyloid in brain has been developed. One hundred percent of animals receiving infusions of synthetic beta-amyloid protein (A beta 1-40) plus a specific heparan sulfate proteoglycan (HSPG) for 1 week or 7 weeks (following 2 week infusions) demonstrated Congo red and thioflavin S-positive deposits adjacent to the infusion site. Extracellular amyloid fibrils were identified by electron microscopy and were immunogold decorated with A beta antibody. Significant increases in Congo red staining were observed in animals infused with A beta plus HSPG versus those infused with only A beta. Infusion of A beta alone was variable with respect to congophilic amyloid persistence, which occurred in 50% of animals and only when endogenous HSPGs accumulated at A beta deposition sites. By 7 weeks, only animals infused with A beta plus HSPG demonstrated compaction of the Congo red material from amorphous, wispy deposits (at 1 week) to stellate deposits resembling a Maltese cross. These spherical amyloid deposits were very similar to Congo red-stained amyloid plaques in human Alzheimer's disease brain, and in vitro data suggest that they were probably formed in vivo following interactions with endogenous brain components.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Encéfalo/metabolismo , Heparitina Sulfato/metabolismo , Proteoglicanas/metabolismo , Peptídeos beta-Amiloides/administração & dosagem , Animais , Benzotiazóis , Encéfalo/ultraestrutura , Vermelho Congo , Glicosaminoglicanos/análise , Glicosaminoglicanos/metabolismo , Proteoglicanas de Heparan Sulfato , Heparitina Sulfato/administração & dosagem , Heparitina Sulfato/isolamento & purificação , Imuno-Histoquímica , Infusões Parenterais , Masculino , Camundongos , Microscopia Eletrônica , Microscopia Imunoeletrônica , Proteoglicanas/administração & dosagem , Proteoglicanas/isolamento & purificação , Ratos , Ratos Sprague-Dawley , Sarcoma Experimental , Técnicas Estereotáxicas , Tiazóis , Fatores de Tempo
5.
Oncogenesis ; 6(9): e377, 2017 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-28892104

RESUMO

Lysine-specific demethylase 1A (LSD1, KDM1A) specifically demethylates di- and monomethylated histones H3K4 and K9, resulting in context-dependent transcriptional repression or activation. We previously identified an irreversible LSD1 inhibitor T-3775440, which exerts antileukemic activities in a subset of acute myeloid leukemia (AML) cell lines by inducing cell transdifferentiation. The NEDD8-activating enzyme inhibitor pevonedistat (MLN4924, TAK-924) is an investigational drug with antiproliferative activities in AML, and is also reported to induce cell differentiation. We therefore tested the combination of these two agents in AML models. The combination treatment resulted in synergistic growth inhibition of AML cells, accompanied by enhanced transdifferentiation of an erythroid leukemia lineage into granulomonocytic-like lineage cells. In addition, pevonedistat-induced rereplication stress during the S phase was greatly augmented by concomitant treatment with T-3775440, as reflected by the increased induction of apoptosis. We further demonstrated that the combination treatment was markedly effective in subcutaneous tumor xenograft models as well as in a disseminated model of AML, leading to tumor eradication or prolonged survival in T-3775440/pevonedistat cotreated mice. Our findings indicate the therapeutic potential of the combination of LSD1 inhibitors and pevonedistat for the treatment of AML.

6.
Oncogene ; 35(27): 3514-23, 2016 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-26522722

RESUMO

Tumor-specific alternative splicing is implicated in the progression of cancer, including clear-cell renal cell carcinoma (ccRCC). Using ccRCC RNA sequencing data from The Cancer Genome Atlas, we found that epithelial splicing regulatory protein 2 (ESRP2), one of the key regulators of alternative splicing in epithelial cells, is expressed in ccRCC. ESRP2 mRNA expression did not correlate with the overall survival rate of ccRCC patients, but the expression of some ESRP-target exons correlated with the good prognosis and with the expression of Arkadia (also known as RNF111) in ccRCC. Arkadia physically interacted with ESRP2, induced polyubiquitination and modulated its splicing function. Arkadia and ESRP2 suppressed ccRCC tumor growth in a coordinated manner. Lower expression of Arkadia correlated with advanced tumor stages and poor outcomes in ccRCC patients. This study thus reveals a novel tumor-suppressive role of the Arkadia-ESRP2 axis in ccRCC.


Assuntos
Carcinoma de Células Renais/genética , Neoplasias Renais/genética , Proteínas Nucleares/genética , Proteínas de Ligação a RNA/genética , Ubiquitina-Proteína Ligases/genética , Processamento Alternativo , Western Blotting , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Proliferação de Células/genética , Progressão da Doença , Células Epiteliais/metabolismo , Perfilação da Expressão Gênica/métodos , Regulação Neoplásica da Expressão Gênica , Ontologia Genética , Células HEK293 , Humanos , Estimativa de Kaplan-Meier , Neoplasias Renais/metabolismo , Neoplasias Renais/patologia , Células MCF-7 , Proteínas Nucleares/metabolismo , Prognóstico , Ligação Proteica , Interferência de RNA , Proteínas de Ligação a RNA/metabolismo , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Ubiquitina-Proteína Ligases/metabolismo , Ubiquitinação
7.
J Neurosci ; 19(19): 8389-400, 1999 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-10493740

RESUMO

A developmentally regulated Homer/Vesl isoform, Cupidin (Homer 2a/Vesl-2Delta11), was isolated from postnatal mouse cerebellum using a fluorescent differential display strategy. The strongest expression of Cupidin was detected in the cerebellar granule cells at approximately postnatal day 7. Cupidin was enriched in the postsynaptic density fraction, and its immunoreactivity was concentrated at glomeruli of the inner granular layer when active synaptogenesis occurred. Cupidin protein could be divided into two functional domains: the N-terminal portion, which was highly conserved among Homer/Vesl family proteins, and the C-terminal portion, which consisted of a putative coiled-coil structure, including several leucine zipper motifs. The N-terminal fragment of Cupidin, which was able to associate with metabotropic glutamate receptor 1 (mGluR1), also interacted with F-actin in vitro. In keeping with this, F-actin immunocytochemically colocalized with Cupidin in cultured cerebellar granule cells, and a Cupidin-mGluR1-actin complex was immunoprecipitated from crude cerebellar lysates using an anti-Cupidin antibody. On the other hand, the C-terminal portion of Cupidin bound to Cdc42, a member of Rho family small GTPases, in a GTP-dependent manner in vitro, and Cupidin functionally interacted with activated-Cdc42 in a heterologous expression system. Together, our findings indicate that Cupidin may serve as a postsynaptic scaffold protein that links mGluR signaling with actin cytoskeleton and Rho family proteins, perhaps during the dynamic phase of morphological changes that occur during synapse formation in cerebellar granule cells.


Assuntos
Actinas/metabolismo , Envelhecimento/metabolismo , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , Córtex Cerebelar/metabolismo , GTP Fosfo-Hidrolases/metabolismo , Regulação da Expressão Gênica no Desenvolvimento , Neurônios/metabolismo , Neuropeptídeos/genética , Neuropeptídeos/metabolismo , Proteínas/metabolismo , Transcrição Gênica , Sequência de Aminoácidos , Animais , Sítios de Ligação , Proteínas de Transporte/química , Córtex Cerebelar/citologia , Córtex Cerebelar/crescimento & desenvolvimento , Clonagem Molecular , Sequência Conservada , Citoesqueleto/fisiologia , Proteínas Ativadoras de GTPase , Proteínas de Arcabouço Homer , Camundongos , Dados de Sequência Molecular , Neurônios/citologia , Neuropeptídeos/química , Receptores de Glutamato Metabotrópico/metabolismo , Proteínas Recombinantes de Fusão/química , Proteínas Recombinantes de Fusão/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
8.
Biochim Biophys Acta ; 1442(2-3): 161-9, 1998 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-9804939

RESUMO

Alternative oxidase (AOX) is dramatically induced when the fungus Magnaporthe grisea is incubated with the fungicide SSF-126, which interacts with the cytochrome bc1 complex in the electron transport system of mitochondria. A full-length cDNA for the alternative oxidase gene (AOX) was obtained, and the deduced amino acid sequence revealed marked similarity to other AOXs, but lacks two cysteine residues at corresponding sites which are conserved in plant AOXs and play essential roles in the post-translational regulation. Northern blot experiments showed that treatment of M. grisea cells with SSF-126 induces accumulation of AOX mRNA in a dose-dependent manner, and the level was correlated with the activity of alternative respiration. H2O2 also induced the accumulation of the transcript with a short half-life (<15 min). Nuclear run-on experiments showed that the AOX gene was transcribed constitutively in unstimulated cells. Cycloheximide did not change the basal level of transcription, but induced the accumulation of the transcript, indicating that active degradation of the transcript occurs by factor(s) sensitive to cycloheximide. On the other hand, SSF-126 enhanced the transcriptional activity of AOX gene threefold compared to that of control cells, and H2O2 was also potent for enhancement of the transcription. From these results, it is concluded that the respiratory inhibitor-dependent activation of the transcription is a primary determinant for the induction of alternative respiration in M. grisea. Because we have previously shown that SSF-126 treatment of M. grisea mitochondria induced the generation of superoxide, active oxygen species are thought to be signal mediators to activate AOX gene transcription in M. grisea.


Assuntos
Fungicidas Industriais/farmacologia , Regulação Fúngica da Expressão Gênica/efeitos dos fármacos , Peróxido de Hidrogênio/farmacologia , Magnaporthe/genética , Oxirredutases/genética , Ativação Transcricional , Sequência de Aminoácidos , Arabidopsis/enzimologia , Clonagem Molecular , Sequência Conservada , Cicloeximida/farmacologia , Transporte de Elétrons/efeitos dos fármacos , Complexo III da Cadeia de Transporte de Elétrons/efeitos dos fármacos , Complexo III da Cadeia de Transporte de Elétrons/metabolismo , Regulação Enzimológica da Expressão Gênica/efeitos dos fármacos , Magnaporthe/efeitos dos fármacos , Magnaporthe/enzimologia , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/metabolismo , Proteínas Mitocondriais , Dados de Sequência Molecular , Oxirredutases/biossíntese , Consumo de Oxigênio , Proteínas de Plantas , Reação em Cadeia da Polimerase , Biossíntese de Proteínas , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos , Ativação Transcricional/efeitos dos fármacos
9.
Circulation ; 104(10): 1171-5, 2001 Sep 04.
Artigo em Inglês | MEDLINE | ID: mdl-11535575

RESUMO

BACKGROUND: Excessive production of nitric oxide (NO) by the inducible isoform of NO synthase (iNOS) is critically involved in endotoxin (ET)-induced hypotension. Tumor necrosis factor-alpha (TNF-alpha) plays an important role in induction of iNOS. Because activated protein C (APC), a physiological anticoagulant, inhibits TNF-alpha production, it might prevent hypotension by inhibiting excessive production of NO. In this study, we examined this possibility using a rat model of septic shock. METHODS AND RESULTS: Intravenous administration of APC prevented both ET-induced hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-). The hypotension was also inhibited when APC was administered 30 minutes after ET administration. APC inhibited the increases in lung levels of iNOS activity by inhibiting expression of iNOS mRNA in animals given ET. APC significantly inhibited the increases in lung tissue levels of TNF-alpha and expression of TNF-alpha mRNA in animals given ET. Neither DEGR-F.Xa, a selective inhibitor of thrombin generation, nor DIP-APC, an active site-blocked APC, showed any effect on these ET-induced changes. Both inhibition of TNF-alpha production by leukocytopenia and treatment with anti-rat TNF-alpha antibody produced effects similar to those induced by APC. Aminoguanidine, a selective inhibitor of iNOS, inhibited both the hypotension and the increases in plasma levels of NO(2)(-)/NO(3)(-) in this animal model. CONCLUSIONS: These observations strongly suggest that APC inhibits iNOS induction by decreasing TNF-alpha production, leading to the prevention of ET-induced hypotension. Furthermore, such effects of APC were not dependent on its anticoagulant effects but rather on its serine protease activity.


Assuntos
Endotoxinas/administração & dosagem , Hipotensão/prevenção & controle , Óxido Nítrico/metabolismo , Proteína C/farmacologia , Clorometilcetonas de Aminoácidos/química , Animais , Anticorpos/farmacologia , Pressão Sanguínea/efeitos dos fármacos , Compostos de Dansil/química , Fator Xa/química , Fator Xa/farmacologia , Hipotensão/induzido quimicamente , Hipotensão/metabolismo , Injeções Intravenosas , Isoflurofato/química , Leucopenia/fisiopatologia , Pulmão/efeitos dos fármacos , Pulmão/enzimologia , Pulmão/metabolismo , Masculino , Nitratos/sangue , Óxido Nítrico Sintase/efeitos dos fármacos , Óxido Nítrico Sintase/genética , Óxido Nítrico Sintase/metabolismo , Óxido Nítrico Sintase Tipo II , Nitritos/sangue , Proteína C/química , RNA Mensageiro/efeitos dos fármacos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ratos , Ratos Wistar , Organismos Livres de Patógenos Específicos , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/imunologia , Fator de Necrose Tumoral alfa/metabolismo
10.
J Bone Miner Res ; 16(11): 2043-9, 2001 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-11697800

RESUMO

The mouse calvarial osteoblast MC3T3-E1 cells released 92 kDa and 68 kDa of gelatinase activities into the conditioned media (CMs) from undifferentiated cells. When differentiation was induced by cultivating cells with ascorbate-2-phosphate (AscP), 68-kDa activity increased significantly in parallel with production of 60-kDa activity. These enzymes required Ca2+ and Zn2+ ions for their proteolytic activities. The 68-kDa activity was immunologically identified as latent matrix metalloproteinase 2 (MMP-2). The 92-kDa activity was deduced to be latent MMP-9 based on its molecular mass. The 60-kDa activity band was found to possess both gelatin and beta-casein hydrolyzing activities, indicating that this activity band might comprise the active form of MMP-2 and latent MMP-13. MC3T3-E1 cells were found to express MMP-2, MMP-13, and membrane type (MT)1-MMP genes by Northern blotting. MMP-2 was expressed constitutively. MMP-13 was up-regulated during the growth with AscP. MT1-MMP expression also was modulated by AscP; at the early stage of differentiation, its messenger RNA (mRNA) level increased and then decreased gradually to the control level. These changes in the profiles of MMPs observed here could be attributed to the maturation of collagenous extracellular matrix (ECM) induced by AscP.


Assuntos
Ácido Ascórbico/farmacologia , Metaloproteinases da Matriz/genética , Metaloproteinases da Matriz/metabolismo , Osteoblastos/efeitos dos fármacos , Osteoblastos/enzimologia , Células 3T3 , Animais , Diferenciação Celular/efeitos dos fármacos , Colagenases/genética , Colagenases/metabolismo , Matriz Extracelular/enzimologia , Expressão Gênica/efeitos dos fármacos , Metaloproteinase 13 da Matriz , Metaloproteinase 2 da Matriz/genética , Metaloproteinase 2 da Matriz/metabolismo , Metaloproteinase 9 da Matriz/genética , Metaloproteinase 9 da Matriz/metabolismo , Camundongos , Osteoblastos/citologia , RNA Mensageiro/genética , RNA Mensageiro/metabolismo
11.
Int J Biochem Cell Biol ; 29(4): 575-82, 1997 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-9363634

RESUMO

In an attempt to characterize a gene(s), of which the expression is ascorbate-dependent, a cDNA fragment encoding ubiquitin was isolated from a subtracted cDNA library constructed from spleen RNAs of ascorbate-deficient or -replete guinea pigs. On Northern blot analysis, three transcripts (1.8 kb ubiX, 1.3 kb ubiY and 0.7 kb ubiZ) were detected. The ubiY encodes four direct repeats of the 76 amino acid ubiquitin sequence with seven additional amino acids, V-Y-A-S-P-I-F, at the C-terminus. The transcript ubiX appears to comprise more than five repeats of the ubiquitin-encoding unit. The ubiZ encodes a ubiquitin monomer fused to an 80 amino acid extension exhibiting 100% amino acid sequence identity to the human homolog, HUMUBA80R. The ubiX gene was expressed animal-dependently. The ubiY mRNA levels decreased under ascorbate-deficient conditions, and increased under ascorbate-replete conditions, whereas ubiZ mRNA remained unaltered at low levels under the feeding conditions used here.


Assuntos
Ácido Ascórbico/metabolismo , Regulação da Expressão Gênica , RNA Mensageiro/análise , Baço/metabolismo , Ubiquitinas/genética , Ubiquitinas/metabolismo , Sequência de Aminoácidos , Animais , Sequência de Bases , DNA Complementar/análise , DNA Complementar/genética , Feminino , Cobaias , Humanos , Dados de Sequência Molecular , Especificidade de Órgãos
12.
Gene ; 251(2): 175-86, 2000 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-10876094

RESUMO

Cis-retinol/androgen dehydrogenase type 2 (CRAD2) has been shown to catalyze the dehydrogenation of retinols, including 9-cis retinol, and also to exhibit 3alpha- and 17beta- hydroxysteroid dehydrogenase activities. To examine the function of this enzyme and regulation of its gene, the Crad2 gene was cloned from a mouse genomic DNA library and characterized. The complete mouse CRAD2-coding region was found in four exons spanning an approximately 5kb region. The nucleotide sequences of the exons encoding 316 amino acids were identical to those of the previously reported mouse Crad2 cDNA. Primer extension analysis and RNase protection assay were used to map the major transcription initiation sites to the positions lying 87 and 89 base pairs upstream of the ATG translation start codon. The region proximal to the initiation sites exhibited the absence of both TATAA and CAAT boxes. This region had hepatocyte nuclear factor binding sites, consistent with its predominant expression in the liver. Computer analysis of an approximately 7.5kb 5'-flanking region also suggested the presence of binding sites for AP-1, SREBP1, HSF2, c-Rel, c-Myc, CREBP, GATA, Ets, E2F, and Oct-1, suggesting that various factors including retinoic acid, cholesterol, various kinds of stress, the cell cycle, and cyclic AMP may regulate the expression of this gene. Fluorescence in-situ hybridization analysis showed that Crad2 is located at the terminus of mouse chromosome 10, an area that corresponds to band 10D3, suggesting that RDH-related SDRs may be located together in the cluster locus. Northern blot hybridization and RT-PCR analysis demonstrated that CRAD2 was expressed not in early embryonic stages, and not in embryonic stem cells, but instead in the gastrointestinal tract during later embryonic development and adult stage. In conclusion, we have presented the first complete structural analysis, including that of the promoter and chromosomal location, of a member of the retinol/androgen dehydrogenase subfamily of the group of the short-chain dehydrogenase/reductase (SDR) isozymes. Our findings will provide the basis for in-vitro or in-vivo studies concerning the regulation of retinol and androgen metabolism and enable determination of the mechanism of diseases related to retinol, retinal, retinoic acid, and androgen.


Assuntos
Oxirredutases do Álcool/genética , Genes/genética , Regiões Promotoras Genéticas , Sequência de Aminoácidos , Animais , Sequência de Bases , Células Cultivadas , Mapeamento Cromossômico , DNA/química , DNA/genética , Embrião de Mamíferos/citologia , Embrião de Mamíferos/enzimologia , Regulação da Expressão Gênica no Desenvolvimento , Regulação Enzimológica da Expressão Gênica , Hibridização in Situ Fluorescente , Isoenzimas/genética , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Endogâmicos , Dados de Sequência Molecular , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Análise de Sequência de DNA , Distribuição Tecidual , Transcrição Gênica
13.
FEBS Lett ; 305(3): 217-9, 1992 Jul 06.
Artigo em Inglês | MEDLINE | ID: mdl-1299619

RESUMO

CAP-50, a calcyclin-associated protein with an apparent molecular mass of 50 kDa, was purified and proved to be a novel annexin [Tokumitsu, H. et al. (1992) J. Biol. Chem. 267, 8919-8924]. We examined the binding of CAP-50 to other Ca(2+)-binding proteins which have two of four EF-hand structures, by a co-precipitation assay with phospholipid (phosphatidylserine). Among nine Ca(2+)-binding proteins (calcyclin, S-100 proteins, p11, calgizzarin, calvasculin, calmodulin and troponin C) examined, only calcyclin interacted with CAP-50. These results clearly show that the interaction of CAP-50 to calcyclin is specific, i.e. other Ca(2+)-binding proteins with the EF-hand structure could not substitute for calcyclin, thereby suggesting the possible role in specific regulation of the function of CAP-50 by Ca2+/calcyclin.


Assuntos
Anexinas/metabolismo , Proteínas de Ligação ao Cálcio/metabolismo , Proteínas S100 , Animais , Precipitação Química , Ligação Proteica , Coelhos
14.
Fungal Genet Biol ; 22(3): 221-8, 1997 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-9454649

RESUMO

The phytopathogenic fungus Magnaporthe grisea has a cyanide-resistant respiratory pathway. The fungicide SSF-126 ((E)-2-methoxyimino-N-methyl-2-(2-phenoxyphenyl) acetamide) blocks the cytochrome electron transport of M. grisea and induces the alternative respiratory pathway. Twelve mutants of M. grisea more susceptible to SSF-126 than wild type were identified after N-methyl-N'-nitro-N-nitrosoguanidine mutagenesis. Five mutants retained a reduced alternative respiration activity, and seven mutants lacked alternative pathway activity. A monoclonal antibody against the maize alternative oxidase cross-reacted against a 40-kDa mitochondrial protein of M. grisea, indicating that the 40-kDa protein is an alternative oxidase. Immunoblot analysis indicated that the seven completely deficient mutants grouped into two classes: four mutants produced the 40-kDa proteins while the other three mutants failed to produce the functional protein. Copyright 1997 Academic Press. Copyright 1997 Academic Press

15.
Neuropharmacology ; 33(7): 847-52, 1994 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-7969803

RESUMO

The role of the muscarinic cholinergic system in the generation of LTP in the medial perforant path-dentate granule cell synapses in vivo was investigated using anesthetized rats. Cholinergic denervation with AF64A, a cholinergic toxin, did not significantly affect LTP induced by a strong tetanus (100 pulses at 100 Hz), but attenuated the LTP induced by a weak tetanus (30 pulses at 60 Hz). The i.c.v. injection of scopolamine (1.5-50 nmol) did not significantly affect the LTP induced by the strong tetanus but attenuated the magnitude of LTP produced by the weak tetanus in a concentration-dependent manner. These results suggest that the cholinergic system is not essential for induction of LTP by strong stimuli but plays a role in facilitating the generation of LTP by weak stimuli. Furthermore, the induction of LTP by a weak tetanus was blocked by pirenzepine but affected by neither AF-DX116 nor 4-diphenylacetoxy-N-methylpiperidine. The LTP-facilitatory action of the cholinergic system is probably mediated by muscarinic M1 receptors.


Assuntos
Hipocampo/efeitos dos fármacos , Potenciação de Longa Duração/efeitos dos fármacos , Receptores Muscarínicos/fisiologia , Animais , Potenciais Evocados/efeitos dos fármacos , Injeções Intraventriculares , Masculino , Antagonistas Muscarínicos , Parassimpatolíticos/farmacologia , Piperidinas/administração & dosagem , Piperidinas/farmacologia , Pirenzepina/administração & dosagem , Pirenzepina/análogos & derivados , Pirenzepina/farmacologia , Ratos , Ratos Wistar , Escopolamina/administração & dosagem , Escopolamina/farmacologia
16.
J Biochem ; 110(3): 457-61, 1991 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-1769973

RESUMO

The lipase production of a plant pathogenic fungus, Fusarium oxysporum f. sp. lini SUF 402, was induced by fat as the carbon source, and its release was stimulated by the infusion of intracellular free calcium ion with a calcium ionophore, A23187. N-(6-Aminohexyl)-5-chloro-1-naphthalenesulfonamide (W-7, a calmodulin inhibitor) and 1-[N,O-bis(5-isoquinolinesulfonyl)-N-methyl- L-tyrosyl]-4-phenylpiperazine (KN-62, a Ca2+/calmodulin dependent protein kinase II inhibitor) reduced the extracellular release of lipase in vivo. 1-(5-Isoquinolinylsulfonyl)-2-methylpiperazine (H-7, a protein kinase C inhibitor) did not have this ability. After K2H32PO4 had been incorporated into the cells, they were treated with W-7 or KN-62 and stimulated by Ca2+ ionophore. On SDS-PAGE of intracellular proteins followed by autoradiography, W-7- and KN-62-treated cells showed inhibition of the incorporation of 32Pi into the 20 kDa protein resulting from Ca2+ stimulation. F. oxysporum had calmodulin (CaM)-dependent protein kinase activity in the cytoplasmic fraction and had the ability to phosphorylate of syntide 2, a specific substrate of CaM kinase II. The partially purified CaM-dependent protein kinase was inhibited by 10 microM KN-62 in vitro. Increase of the intracellular Ca2+ concentration of F. oxysporum activated CaM and CaM-dependent protein kinase, resulting in the extracellular lipase release. These results suggest the existence of a Ca2+ signalling system in F. oxysporum like those observed in higher eucaryotes.


Assuntos
Cálcio/farmacologia , Fusarium/enzimologia , Lipase/metabolismo , 1-(5-Isoquinolinasulfonil)-2-Metilpiperazina , Calcimicina/farmacologia , Cálcio/metabolismo , Calmodulina/antagonistas & inibidores , Fusarium/efeitos dos fármacos , Isoquinolinas/farmacologia , Cinética , Piperazinas/farmacologia , Inibidores de Proteínas Quinases , Frações Subcelulares/enzimologia , Sulfonamidas/farmacologia
17.
J Biochem ; 78(4): 697-703, 1975 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-1213988

RESUMO

It has previously been shown in our laboratory that the hypocalcemic substances purified from the thymus have a potent lymphocyte-increasing action in mice. Then, lymphocyte-increasing activity was examined with bovine parotid gland extracts, which showed a hypocalcemic activity as potent as that of the thymus extracts. The lymphocyte-increasing activity was assayed in the littermates of neonatal mice of Swiss-Webster strain; the materials used for this experiment were purified preparations and several fractions obtained from the parotid gland extracts in the course of purification. It was found that the potency of lymphocyte-increasing activity rose approximately in parallel with the rise in hypocalcemic activity with progress in purification. The final product, which was purified from the gland by isoelectric precipitation at pH 5.4, fractional precipitation with ammonium sulfate, chromatography on DEAE-cellulose, gel filtration on Sepharose 6B and preparative disc electrophoresis, gave a single band in polyacrylamide gel electrophoresis. Its intravenous injection in rabbits, in a dose of 10 mug/kg, produced a significant lowering in serum calcium (percent decrease 10.24 +/- 1.06%) compared with control animals given an injection of physiological saline. Intraperitoneal injection of this purified product, in a dose of 0.5 mug/mouse, in the littermates of neonatal mice, also produced a significant increase (ratio of lymphocytes to polymorphs 2.47 +/- 0.07) in lymphocytes compared with control animals injected with physiological saline (L/P ratio 1.57 +/- 0.05). These facts suggest that this purified protein fraction inherently contains both activities, but the possibility cannot be ruled out of slight contamination by a substance having a high activity. On the other hand, a fraction having no activity for lowering serum calcium but which had activity for increasing the lymphocytes was obtained. This is the first paper to report the presence of lymphocyte-increasing substances in the bovine parotid gland and the purification of one of the substances from the gland.


Assuntos
Hipocalcemia/etiologia , Linfócitos/metabolismo , Glândula Parótida/fisiologia , Animais , Bovinos , Relação Dose-Resposta a Droga , Contagem de Leucócitos , Camundongos , Coelhos , Extratos de Tecidos
18.
Virchows Arch ; 427(4): 395-400, 1995.
Artigo em Inglês | MEDLINE | ID: mdl-8548124

RESUMO

A major constituent of the amyloid fibrils in dialysis-related amyloidosis is beta 2-microglobulin (beta 2-MG). Heparan sulphates (HS) co-localize with the amyloid fibrils and monocytes/macrophages are commonly found around amyloid deposits, but the role of HS in amyloidogenesis is not yet defined. HS have variable saccharide sequences and can interact specifically with basic fibroblast growth factor (bFGF), a potent chemotactic factor for the monocyte/macrophage. The present investigation was undertaken to look for a functional link between co-localized HS and the pathogenesis of dialysis-related amyloidosis. Using amyloid-enriched ligament, immunohistochemical localization was tested for beta 2-MG, endogenous bFGF, and bFGF-binding portions of HS. For the detection of bFGF-binding portions of HS, the ligament sections were incubated with exogenous bFGF and then with anti-bFGF antibody. The specificity of the interaction between bFGF and HS was established by confirming a concomitant loss of immunoreactivity during selective removal of HS with heparitinase. beta 2-MG, endogenous bFGF, and bFGF-binding portions of HS were detected between bundles of collagen. Endogenous bFGF and bFGF-binding portions of HS were not detected in more advanced amyloid lesions, whereas beta 2-MG and other portions of HS were detected. We propose that beta 2-MG, endogenous bFGF, and bFGF-binding portions of HS form a complex and localize in the early amyloid lesions of dialysis-related amyloidosis.


Assuntos
Amiloidose , Fator 2 de Crescimento de Fibroblastos/análise , Heparitina Sulfato/análise , Falência Renal Crônica/terapia , Ligamentos/química , Diálise Renal/efeitos adversos , Amiloidose/etiologia , Sítios de Ligação , Fator 2 de Crescimento de Fibroblastos/metabolismo , Heparitina Sulfato/metabolismo , Humanos , Microglobulina beta-2/análise , Microglobulina beta-2/metabolismo
19.
Ann N Y Acad Sci ; 249: 220-35, 1975 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-1055570

RESUMO

Two kinds of active protein fraction, TP1 and TP2, were isolated from bovine thymus extracts. Both these fractions showed a single band in polyacrylamide gel disc electrophoresis. Though these two fractions showed a difference in potency, they both lowered serum calcium in rabbits and increased lymphocytes in mice. Molecular weight determination by SDS polyacrylamide gel electrophoresis gave the values of 68,000 for TP1 and 57,000 for TP2. Amino acid composition of TP1 did not show marked characteristics but was clearly different from that of bovine serum albumin. Isoelectric focusing showed the isoelectric point at pH 5.65 for TP1 and pH 5.4 for TP2. Dose-response relation in serum calcium-lowering activity was examined with a sample purified from the extracts, and a linear dependence of the response to log dose was recognized over a moderate range of doses. The time-course measurement of the hypocalcemic activity showed that the action of TP1 is somewhat different from that of calcitonin.


Assuntos
Cálcio/sangue , Ativação Linfocitária , Extratos do Timo/isolamento & purificação , Timo/imunologia , Aminoácidos/análise , Animais , Bovinos , Cromatografia , Cromatografia DEAE-Celulose , Eletroforese Descontínua , Glucose/análise , Hipocalcemia/induzido quimicamente , Focalização Isoelétrica , Contagem de Leucócitos , Peso Molecular , Proteínas/análise , Coelhos , Sefarose , Dodecilsulfato de Sódio
20.
Ann N Y Acad Sci ; 845: 219-24, 1998 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-9668355

RESUMO

To address the role of brain gangliosides in synaptic activity, the ceramide analogs, D-threo-1-phenyl-2-decanoylamino-3-morpholino-1-propanol (D-PDMP) and its enantiomer, L-PDMP, were used to inhibit and stimulate ganglioside biosynthesis in cultured cortical neurons. Prolonged treatment with both PDMP isomers exhibited opposite effects on functional synapse formation measured by spontaneous synchronized oscillatory activity of intracellular Ca2+ between the neurons: suppression by D-PDMP and facilitation by L-PDMP. Up-regulation of synaptic activity by L-PDMP could be correlated with the slow but robust activation of p42 mitogen-activated protein kinase. Treatment with L-PDMP after transient forebrain ischemia in rats ameliorated the deficit of a well-learned spatial memory by an 8-arm maze task, suggesting a new potential therapeutic approach for neurodegenerative disorders.


Assuntos
Gangliosídeos/metabolismo , Morfolinas/farmacologia , Neurônios/fisiologia , Sinapses/fisiologia , Animais , Cálcio/metabolismo , Células Cultivadas , Córtex Cerebral/citologia , Córtex Cerebral/fisiologia , Inibidores Enzimáticos/farmacologia , Memória/efeitos dos fármacos , Camundongos , Proteína Quinase 1 Ativada por Mitógeno/metabolismo , Neurônios/efeitos dos fármacos , Ratos , Estereoisomerismo , Sinapses/efeitos dos fármacos
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