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61.
Simon Schafferer Rimpi Khurana Violetta Refolo Serena Venezia Edith Sturm Paolo Piatti Clara Hechenberger Hubert Hackl Roman Kessler Michaela Willi Ronald Gstir Anne Krogsdam Alexandra Lusser Werner Poewe Gregor K. Wenning Alexander Hüttenhofer Nadia Stefanova 《PloS one》2016,11(3)
Multiple system atrophy (MSA) is a fatal rapidly progressive α-synucleinopathy, characterized by α-synuclein accumulation in oligodendrocytes. It is accepted that the pathological α-synuclein accumulation in the brain of MSA patients plays a leading role in the disease process, but little is known about the events in the early stages of the disease. In this study we aimed to define potential roles of the miRNA-mRNA regulatory network in the early pre-motor stages of the disease, i.e., downstream of α-synuclein accumulation in oligodendroglia, as assessed in a transgenic mouse model of MSA. We investigated the expression patterns of miRNAs and their mRNA targets in substantia nigra (SN) and striatum, two brain regions that undergo neurodegeneration at a later stage in the MSA model, by microarray and RNA-seq analysis, respectively. Analysis was performed at a time point when α-synuclein accumulation was already present in oligodendrocytes at neuropathological examination, but no neuronal loss nor deficits of motor function had yet occurred. Our data provide a first evidence for the leading role of gene dysregulation associated with deficits in immune and inflammatory responses in the very early, non-symptomatic disease stages of MSA. While dysfunctional homeostasis and oxidative stress were prominent in SN in the early stages of MSA, in striatum differential gene expression in the non-symptomatic phase was linked to oligodendroglial dysfunction, disturbed protein handling, lipid metabolism, transmembrane transport and altered cell death control, respectively. A large number of putative miRNA-mRNAs interaction partners were identified in relation to the control of these processes in the MSA model. Our results support the role of early changes in the miRNA-mRNA regulatory network in the pathogenesis of MSA preceding the clinical onset of the disease. The findings thus contribute to understanding the disease process and are likely to pave the way towards identifying disease biomarkers for early diagnosis of MSA. 相似文献
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Purification, Characterization, and Functional Role of a Novel Extracellular Protease from Pleurotus ostreatus 总被引:3,自引:0,他引:3
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Gianna Palmieri Carmen Bianco Giovanna Cennamo Paola Giardina Gennaro Marino Maria Monti Giovanni Sannia 《Applied microbiology》2001,67(6):2754-2759
A new extracellular protease (PoSl; Pleurotus ostreatus subtilisin-like protease) from P. ostreatus culture broth has been purified and characterized. PoSl is a monomeric glycoprotein with a molecular mass of 75 kDa, a pI of 4.5, and an optimum pH in the alkaline range. The inhibitory profile indicates that PoSl is a serine protease. The N-terminal and three tryptic peptide sequences of PoSl have been determined. The homology of one internal peptide with conserved sequence around the Asp residue of the catalytic triad in the subtilase family suggests that PoSl is a subtilisin-like protease. This hypothesis is further supported by the finding that PoSl hydrolysis sites of the insulin B chain match those of subtilisin. PoSl activity is positively affected by calcium. A 10-fold decrease in the Km value in the presence of calcium ions can reflect an induced structural change in the substrate recognition site region. Furthermore, Ca2+ binding slows PoSl autolysis, triggering the protein to form a more compact structure. These effects have already been observed for subtilisin and other serine proteases. Moreover, PoSl protease seems to play a key role in the regulation of P. ostreatus laccase activity by degrading and/or activating different isoenzymes. 相似文献
64.
VGJ phi, a novel filamentous phage of Vibrio cholerae, integrates into the same chromosomal site as CTX phi
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Campos J Martínez E Suzarte E Rodríguez BL Marrero K Silva Y Ledón T del Sol R Fando R 《Journal of bacteriology》2003,185(19):5685-5696
We describe a novel filamentous phage, designated VGJ phi, isolated from strain SG25-1 of Vibrio cholerae O139, which infects all O1 (classical and El Tor) and O139 strains tested. The sequence of the 7,542 nucleotides of the phage genome reveals that VGJ phi has a distinctive region of 775 nucleotides and a conserved region with an overall genomic organization similar to that of previously characterized filamentous phages, such as CTX phi of V. cholerae and Ff phages of Escherichia coli. The conserved region carries 10 open reading frames (ORFs) coding for products homologous to previously reported peptides of other filamentous phages, and the distinctive region carries one ORF whose product is not homologous to any known peptide. VGJ phi, like other filamentous phages, uses a type IV pilus to infect V. cholerae; in this case, the pilus is the mannose-sensitive hemagglutinin. VGJ phi-infected V. cholerae overexpresses the product of one ORF of the phage (ORF112), which is similar to single-stranded DNA binding proteins of other filamentous phages. Once inside a cell, VGJ phi is able to integrate its genome into the same chromosomal attB site as CTX phi, entering into a lysogenic state. Additionally, we found an attP structure in VGJ phi, which is also conserved in several lysogenic filamentous phages from different bacterial hosts. Finally, since different filamentous phages seem to integrate into the bacterial dif locus by a general mechanism, we propose a model in which repeated integration events with different phages might have contributed to the evolution of the CTX chromosomal region in V. cholerae El Tor. 相似文献
65.
Therapeutic targeting of innate immunity with Toll-like receptor agonists and antagonists 总被引:10,自引:0,他引:10
The identification of the antigen recognition receptors for innate immunity, most notably the Toll-like receptors, has sparked great interest in therapeutic manipulation of the innate immune system. Toll-like receptor agonists are being developed for the treatment of cancer, allergies and viral infections, and as adjuvants for potent new vaccines to prevent or treat cancer and infectious diseases. As recognition grows of the role of inappropriate Toll-like receptor stimulation in inflammation and autoimmunity, significant efforts have begun to develop antagonists to Toll-like receptors as well. 相似文献
66.
David Wragg Elizabeth A. J. Cook Perle Latr de Lat Tatjana Sitt Johanneke D. Hemmink Maurine C. Chepkwony Regina Njeru E. Jane Poole Jessica Powell Edith A. Paxton Rebecca Callaby Andrea Talenti Antoinette A. Miyunga Gideon Ndambuki Stephen Mwaura Harriet Auty Oswald Matika Musa Hassan Karen Marshall Timothy Connelley Liam J. Morrison B. Mark deC. Bronsvoort W. Ivan Morrison Philip G. Toye James G. D. Prendergast 《PLoS genetics》2022,18(4)
East Coast fever, a tick-borne cattle disease caused by the Theileria parva parasite, is among the biggest natural killers of cattle in East Africa, leading to over 1 million deaths annually. Here we report on the genetic analysis of a cohort of Bos indicus (Boran) cattle demonstrating heritable tolerance to infection with T. parva (h2 = 0.65, s.e. 0.57). Through a linkage analysis we identify a 6 Mb genomic region on bovine chromosome 15 that is significantly associated with survival outcome following T. parva exposure. Testing this locus in an independent cohort of animals replicates this association with survival following T. parva infection. A stop gained variant in a paralogue of the FAF1 gene in this region was found to be highly associated with survival across both related and unrelated animals, with only one of the 20 homozygote carriers (T/T) of this change succumbing to the disease in contrast to 44 out of 97 animals homozygote for the reference allele (C/C). Consequently, we present a genetic locus linked to tolerance of one of Africa’s most important cattle diseases, raising the promise of marker-assisted selection for cattle that are less susceptible to infection by T. parva. 相似文献
67.
Stacia R Engel Edith D Wong Robert S Nash Suzi Aleksander Micheal Alexander Eric Douglass Kalpana Karra Stuart R Miyasato Matt Simison Marek S Skrzypek Shuai Weng J Michael Cherry 《Genetics》2022,220(4)
Saccharomyces cerevisiae is used to provide fundamental understanding of eukaryotic genetics, gene product function, and cellular biological processes. Saccharomyces Genome Database (SGD) has been supporting the yeast research community since 1993, serving as its de facto hub. Over the years, SGD has maintained the genetic nomenclature, chromosome maps, and functional annotation, and developed various tools and methods for analysis and curation of a variety of emerging data types. More recently, SGD and six other model organism focused knowledgebases have come together to create the Alliance of Genome Resources to develop sustainable genome information resources that promote and support the use of various model organisms to understand the genetic and genomic bases of human biology and disease. Here we describe recent activities at SGD, including the latest reference genome annotation update, the development of a curation system for mutant alleles, and new pages addressing homology across model organisms as well as the use of yeast to study human disease. 相似文献
68.
69.
Zusammenfassung
Anemone apennina gehört in die kleine Grappe der einkeimblättrigen Dikotylen-Arten.Der einzige Kotyledo wird lateral angelegt, drängt aber den Sproßvegetationspunkt später etwas zur Seite. Von der Anlage eines zweiten Kotyledos fehlt jede Spur.Weder der Embryogenese noch der Entwicklungsgeschichte und der Anatomie der Keimpflanzen sind Hinweise für das Vorliegen einer kongenitalen Verwachsung zweier Kotyledonen (Synkotylie) zu entnehmen.Der Kotyledo ist in gerader Linie über dem einen Pol der Xylemplatte der diarchen Keimachsenstele inseriert. Der Kotyledonarstiel wird von einem einfachen Leitstrang durchzogen, der im basalen Teil als diarche Stele und im apikalen als kollaterales Bündel ausgebildet ist. Die Nervatur der zweiteiligen Kotyledonarspreite macht wahrscheinlich, daß es sich um ein asymmetrisch fiederteiliges Blatt handelt.Daraus ergibt sich, daß bei A.apennina eine echte Einkeimblättrigkeit vorliegt, in dem Sinne, daß das einzige Keimblatt einem der beiden Keimblätter verwandter Arten homolog ist.Wir danken der Deutschen Forschungsgemeinschaft für die Unterstützung unserer Arbeiten. 相似文献
70.
Edith Varsavsky 《Mycopathologia》1962,18(4):257-258
Summary
Keratinomyces ajelloi andMicrosporum gypseum have been isolated from soil samples from public gardens and from a breeding-place with rabbits and fowls in the urban zone of the Buenos Aires city, usingVanbreuseghem's technique with hair bait.On the Petri dishes with soil and hair the characteristic cleistotecia of the sexual form were observed. 相似文献