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1.
Acta Neuropathol ; 142(3): 399-421, 2021 09.
Artigo em Inglês | MEDLINE | ID: mdl-34309760

RESUMO

Parkinson's disease (PD) is a progressive neurodegenerative disorder that is neuropathologically characterized by degeneration of dopaminergic neurons of the substantia nigra (SN) and formation of Lewy bodies and Lewy neurites composed of aggregated α-synuclein. Proteolysis of α-synuclein by matrix metalloproteinases was shown to facilitate its aggregation and to affect cell viability. One of the proteolysed fragments, Gln79-α-synuclein, possesses a glutamine residue at its N-terminus. We argue that glutaminyl cyclase (QC) may catalyze the pyroglutamate (pGlu)79-α-synuclein formation and, thereby, contribute to enhanced aggregation and compromised degradation of α-synuclein in human synucleinopathies. Here, the kinetic characteristics of Gln79-α-synuclein conversion into the pGlu-form by QC are shown using enzymatic assays and mass spectrometry. Thioflavin T assays and electron microscopy demonstrated a decreased potential of pGlu79-α-synuclein to form fibrils. However, size exclusion chromatography and cell viability assays revealed an increased propensity of pGlu79-α-synuclein to form oligomeric aggregates with high neurotoxicity. In brains of wild-type mice, QC and α-synuclein were co-expressed by dopaminergic SN neurons. Using a specific antibody against the pGlu-modified neo-epitope of α-synuclein, pGlu79-α-synuclein aggregates were detected in association with QC in brains of two transgenic mouse lines with human α-synuclein overexpression. In human brain samples of PD and dementia with Lewy body subjects, pGlu79-α-synuclein was shown to be present in SN neurons, in a number of Lewy bodies and in dystrophic neurites. Importantly, there was a spatial co-occurrence of pGlu79-α-synuclein with the enzyme QC in the human SN complex and a defined association of QC with neuropathological structures. We conclude that QC catalyzes the formation of oligomer-prone pGlu79-α-synuclein in human synucleinopathies, which may-in analogy to pGlu-Aß peptides in Alzheimer's disease-act as a seed for pathogenic protein aggregation.


Assuntos
Aminoaciltransferases/metabolismo , Sinucleinopatias/genética , alfa-Sinucleína/metabolismo , Animais , Encéfalo/patologia , Sobrevivência Celular , Cromatografia em Gel , Neurônios Dopaminérgicos/metabolismo , Glutamina/metabolismo , Humanos , Cinética , Doença por Corpos de Lewy/genética , Doença por Corpos de Lewy/metabolismo , Camundongos , Camundongos Transgênicos , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Processamento de Proteína Pós-Traducional , Sambucus nigra/citologia , Sambucus nigra/metabolismo
2.
Int J Mol Sci ; 22(11)2021 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-34064208

RESUMO

In Parkinson's disease, aggregates of α-synuclein within Lewy bodies and Lewy neurites represent neuropathological hallmarks. However, the cellular and molecular mechanisms triggering oligomeric and fibrillary α-synuclein aggregation are not fully understood. Recent evidence indicates that oxidative stress induced by metal ions and post-translational modifications such as phosphorylation, ubiquitination, nitration, glycation, and SUMOylation affect α-synuclein conformation along with its aggregation propensity and neurotoxic profiles. In addition, proteolytic cleavage of α-synuclein by specific proteases results in the formation of a broad spectrum of fragments with consecutively altered and not fully understood physiological and/or pathological properties. In the present review, we summarize the current knowledge on proteolytical α-synuclein cleavage by neurosin, calpain-1, cathepsin D, and matrix metalloproteinase-3 in health and disease. We also shed light on the contribution of the same enzymes to proteolytical processing of pathogenic proteins in Alzheimer's disease and report potential cross-disease mechanisms of pathogenic protein aggregation.


Assuntos
alfa-Sinucleína/metabolismo , Doença de Alzheimer/metabolismo , Animais , Humanos , Doença de Parkinson/metabolismo , Peptídeo Hidrolases/metabolismo , Agregados Proteicos/fisiologia , Proteólise
3.
Molecules ; 25(3)2020 Jan 29.
Artigo em Inglês | MEDLINE | ID: mdl-32013170

RESUMO

Alzheimer's disease (AD) and Parkinson's disease (PD), including dementia with Lewy bodies (DLB), account for the majority of dementia cases worldwide. Interestingly, a significant number of patients have clinical and neuropathological features of both AD and PD, i.e., the presence of amyloid deposits and Lewy bodies in the neocortex. The identification of α-synuclein peptides in amyloid plaques in DLB brain led to the hypothesis that both peptides mutually interact with each other to facilitate neurodegeneration. In this article, we report the influence of Aß(1-42) and pGlu-Aß(3-42) on the aggregation of α-synuclein in vitro. The aggregation of human recombinant α-synuclein was investigated using thioflavin-T fluorescence assay. Fibrils were investigated by means of antibody conjugated immunogold followed by transmission electron microscopy (TEM). Our data demonstrate a significantly increased aggregation propensity of α-synuclein in the presence of minor concentrations of Aß(1-42) and pGlu-Aß(3-42) for the first time, but without effect on toxicity on mouse primary neurons. The analysis of the composition of the fibrils by TEM combined with immunogold labeling of the peptides revealed an interaction of α-synuclein and Aß in vitro, leading to an accelerated fibril formation. The analysis of kinetic data suggests that significantly enhanced nucleus formation accounts for this effect. Additionally, co-occurrence of α-synuclein and Aß and pGlu-Aß, respectively, under pathological conditions was confirmed in vivo by double immunofluorescent labelings in brains of aged transgenic mice with amyloid pathology. These observations imply a cross-talk of the amyloid peptides α-synuclein and Aß species in neurodegeneration. Such effects might be responsible for the co-occurrence of Lewy bodies and plaques in many dementia cases.


Assuntos
Peptídeos beta-Amiloides/química , Agregados Proteicos , alfa-Sinucleína/química , Doença de Alzheimer , Amiloide/química , Amiloide/ultraestrutura , Peptídeos beta-Amiloides/metabolismo , Peptídeos beta-Amiloides/farmacologia , Animais , Sobrevivência Celular , Imunofluorescência , Cinética , Corpos de Lewy , Camundongos , Neurônios/metabolismo , Neurônios/patologia , Agregação Patológica de Proteínas , Proteínas Recombinantes/química , Proteínas Recombinantes/metabolismo , alfa-Sinucleína/metabolismo
4.
Laryngorhinootologie ; 99(6): 414-430, 2020 06.
Artigo em Alemão | MEDLINE | ID: mdl-32557461

RESUMO

Due to cholesteatoma's slowly progressive and destructive growth there is a risk of intracranial and potentially life-threatening complications. That's why every cholesteatoma is a basically absolute indication for surgery. Only asymptomatic and small retractions, so-called prae-cholesteatomas, may be under observation. While the first part of this article focused on the basics of pathogenesis and diagnostics, this one provides an overview of current surgical strategies, both proven and new ones.


Assuntos
Colesteatoma da Orelha Média , Colesteatoma , Colesteatoma/cirurgia , Colesteatoma da Orelha Média/cirurgia , Humanos
5.
Chem Senses ; 44(6): 371-377, 2019 07 17.
Artigo em Inglês | MEDLINE | ID: mdl-31046120

RESUMO

To date, most studies on the relationship between chemosensory performance and quality of life have focused on orthonasal measures of olfactory function. In the current investigation, we examined the predictive value of orthonasal and flavor identification indices of olfactory function on a wide spectrum of health and sociopsychological factors, including quality of life, life satisfaction, overall health, and depressive symptoms. Participants were 178 ENT patients (Mage = 58 ± 1), representing various causes of olfactory loss: idiopathic smell loss (n = 51; Mage = 63 ± 2), sinunasal disease (n = 27; Mage = 56 ± 3), head trauma (n = 33; Mage = 51 ± 2), and infections of the upper respiratory tract (n = 67; Mage = 59 ± 2). They completed self-report questionnaires and underwent olfactory testing using Sniffin' Sticks (orthonasal olfactory testing) and "Taste Powder" (intraorally applied flavors for retronasal olfactory testing, additionally inducing taste sensation). Data were analyzed with hierarchical regression models wherein the first step included subjects' sex, age, and orthonasal olfaction score. In the second step, we included the "Taste Powder" score. Tested models revealed that the first step was not significantly predicting variables of interest; however, there was an improvement of the model's predictive value when the "Taste Powder" score was added. Results of this study suggest that flavor identification significantly improves predictions of health and sociopsychological functioning of ENT patients with various etiologies.


Assuntos
Transtornos do Olfato/fisiopatologia , Bulbo Olfatório/fisiopatologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Nariz/fisiopatologia , Qualidade de Vida , Inquéritos e Questionários
6.
Int J Mol Sci ; 20(18)2019 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-31500303

RESUMO

Viral infections are associated with increased incidence of severe sepsis. Particularly during the early stages, type I interferons (IFNs) are known mediators of detrimental effects. However, the functional role of early interferon ß (IFNß) and its cellular source during sepsis in the context of preexisting viral infections has not been defined. Using the colon ascendens stent peritonitis (CASP) model, we demonstrate that IFNß-/- and type I IFN receptor (IFNAR1)-/- mice were less susceptible to sepsis after pre-stimulation with the viral mimetic poly(I:C). Wild type (WT) mice treated with poly(I:C) exhibited altered expression patterns of TNF and IL-12p40 during CASP which were dependent on IFNß or IFNAR1, suggesting a mechanism for the increased sepsis susceptibility of WT mice. Using a double cytokine reporter mouse model, we present novel data on the simultaneous expression of IFNß and IL-12p40 on a single cell level during polymicrobial sepsis in vivo. Conventional dendritic cells (cDCs) were identified as primary source of IFNß and the protective cytokine IL-12p40 after CASP surgery irrespective of poly(I:C) pre-stimulation. These data demonstrated that if polymicrobial sepsis is preceded by a viral infection, IFNß and IL-12p40 are expressed by polyfunctional cDCs suggesting that these cells can play both detrimental and beneficial roles during sepsis development.


Assuntos
Coinfecção/imunologia , Células Dendríticas/imunologia , Interferon beta/genética , Poli I-C/administração & dosagem , Receptor de Interferon alfa e beta/genética , Sepse/imunologia , Animais , Coinfecção/sangue , Coinfecção/virologia , Modelos Animais de Doenças , Feminino , Técnicas de Inativação de Genes , Interferon beta/metabolismo , Subunidade p40 da Interleucina-12/metabolismo , Camundongos , Camundongos Endogâmicos C57BL , Poli I-C/imunologia , Receptor de Interferon alfa e beta/metabolismo , Sepse/virologia , Transdução de Sinais
7.
Laryngorhinootologie ; 98(12): 885-897, 2019 Dec.
Artigo em Alemão | MEDLINE | ID: mdl-31810105

RESUMO

Cholesteatoma is a chronic inflammation of the middle ear, which leads to a progressive bony destruction of the petrous bone. Main symptoms are fetid otorrhea, hearing loss and dizziness. Left untreated, cholesteatoma may be fatal due to intracranial complications. The following overview is intended to illustrate the current and generally recognized knowledge of genesesi, clinical symptoms und preoperative diagnostical procedure. Surgical therapie will be focussed in a second part.


Assuntos
Colesteatoma , Surdez , Orelha Média , Perda Auditiva , Humanos , Osso Petroso
8.
Anal Biochem ; 559: 11-16, 2018 10 15.
Artigo em Inglês | MEDLINE | ID: mdl-30098994

RESUMO

Common assays for endoprotease activity of meprin α and ß are based on cleavage of internally quenched substrates. Although direct and convenient, for meprins these assays bear disadvantages such as, e.g., significant substrate inhibition or potential fluorescence quenching by compounds applied in inhibitor analysis. Here, we present a novel continuous assay by introducing an auxiliary enzyme, prolyl tripeptidyl aminopeptidase (PtP) and the chromogenic substrate KKGYVADAP-p-nitroanilide. We provide a quick strategy for expression and one-step-purification of the auxiliary enzyme. The enzyme kinetic data for meprin α and ß suggest hyperbolic v/S-characteristics, the kinetic parameters of substrate conversion by meprin ß were Km = 184 ±â€¯32 µM and kcat = 20 ±â€¯4 s-1. We also present conditions for the use of the fluorogenic substrate KKGYVADAP-AMC to assess meprin ß activity. The assays were applied for determination of inhibitory parameters of the natural inhibitor actinonin and two recently published hydroxamates. Hence, we present two novel methods, which can be applied to assess inhibitory mechanism and potency with the attractive current drug targets meprin α and ß. Furthermore, the assay might also provide implications for analysis of other endoproteases as well as their inhibitors.


Assuntos
Proteínas de Bactérias/metabolismo , Dipeptidil Peptidases e Tripeptidil Peptidases/metabolismo , Metaloendopeptidases/análise , Porphyromonas gingivalis/enzimologia , Serina Endopeptidases/metabolismo , Proteínas de Bactérias/química , Dipeptidil Peptidases e Tripeptidil Peptidases/química , Relação Dose-Resposta a Droga , Ácidos Hidroxâmicos/farmacologia , Cinética , Metaloendopeptidases/antagonistas & inibidores , Metaloendopeptidases/metabolismo , Estrutura Molecular , Inibidores de Proteases/farmacologia , Serina Endopeptidases/química , Relação Estrutura-Atividade
9.
J Immunol ; 196(11): 4447-51, 2016 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-27183572

RESUMO

Type I IFNs are critical in initiating protective antiviral immune responses, and plasmacytoid dendritic cells (pDCs) represent a major source of these cytokines. We show that only few pDCs are capable of producing IFN-ß after virus infection or CpG stimulation. Using IFNß/YFP reporter mice, we identify these IFN-ß-producing cells in the spleen as a CCR9(+)CD9(-) pDC subset that is localized exclusively within the T/B cell zones. IFN-ß-producing pDCs exhibit a distinct transcriptome profile, with higher expression of genes encoding cytokines and chemokines, facilitating T cell recruitment and activation. These distinctive characteristics of IFN-ß-producing pDCs are independent of the type I IFNR-mediated feedback loop. Furthermore, IFN-ß-producing pDCs exhibit enhanced CCR7-dependent migratory properties in vitro. Additionally, they effectively recruit T cells in vivo in a peritoneal inflammation model. We define "professional type I IFN-producing cells" as a distinct subset of pDCs specialized in coordinating cellular immune responses.


Assuntos
Células Dendríticas/imunologia , Células Dendríticas/metabolismo , Interferon beta/genética , Baço/citologia , Baço/imunologia , Transcriptoma , Animais , Interferon beta/imunologia , Camundongos , Camundongos Endogâmicos C57BL , Camundongos Knockout , Receptor de Interferon alfa e beta/deficiência , Receptor de Interferon alfa e beta/imunologia , Transdução de Sinais
10.
J Nat Prod ; 79(4): 697-703, 2016 Apr 22.
Artigo em Inglês | MEDLINE | ID: mdl-26905390

RESUMO

A series of seven oxyprenylated phenylpropanoids and naphthoquinones were tested regarding their ability to activate transient receptor potential ankyrin subtype 1 channel (TRPA1). Three of the assayed compounds, namely, boropinal (3), juglone (5), and plumbagin (7), acted as strong modulators of TRPA1 channels with EC50 values of 9.8, 1.7, and 0.5 µM, respectively, as assessed by Ca(2+) assays. Moreover, the compounds elicited TRPA1 currents in electrophysiological whole cell recordings. We additionally provide evidence that plumbagin activated TRPA1-positive neurons isolated from mouse dorsal root ganglion neurons but did not affect sensory neurons from TRPA1-deficient mice. The high potencies of plumbagin and juglone to activate TRPA1 channels may explain the molecular basis of the mucosal irritant properties of these compounds as well as of related naphthoquinones and phytopreparations, as widely reported in the literature.


Assuntos
Naftoquinonas/farmacologia , Fenilpropionatos/farmacologia , Canais de Potencial de Receptor Transitório/antagonistas & inibidores , Animais , Anquirinas , Cálcio/análise , Cálcio/metabolismo , Cumarínicos/química , Cumarínicos/farmacologia , Feminino , Gânglios Espinais/efeitos dos fármacos , Células HEK293 , Humanos , Masculino , Camundongos , Estrutura Molecular , Naftoquinonas/química , Fenilpropionatos/química , Células Receptoras Sensoriais/efeitos dos fármacos , Canal de Cátion TRPA1
11.
Neuroimage ; 108: 225-33, 2015 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-25512041

RESUMO

The issue of whether human perception of speech and song recruits integrated or dissociated neural systems is contentious. This issue is difficult to address directly since these stimulus classes differ in their physical attributes. We therefore used a compelling illusion (Deutsch et al. 2011) in which acoustically identical auditory stimuli are perceived as either speech or song. Deutsch's illusion was used in a functional MRI experiment to provide a direct, within-subject investigation of the brain regions involved in the perceptual transformation from speech into song, independent of the physical characteristics of the presented stimuli. An overall differential effect resulting from the perception of song compared with that of speech was revealed in right midposterior superior temporal sulcus/right middle temporal gyrus. A left frontotemporal network, previously implicated in higher-level cognitive analyses of music and speech, was found to co-vary with a behavioural measure of the subjective vividness of the illusion, and this effect was driven by the illusory transformation. These findings provide evidence that illusory song perception is instantiated by a network of brain regions that are predominantly shared with the speech perception network.


Assuntos
Percepção Auditiva/fisiologia , Mapeamento Encefálico/métodos , Encéfalo/fisiologia , Estimulação Acústica/métodos , Feminino , Humanos , Ilusões , Processamento de Imagem Assistida por Computador , Imageamento por Ressonância Magnética , Masculino , Adulto Jovem
12.
J Hered ; 105(1): 1-18, 2014.
Artigo em Inglês | MEDLINE | ID: mdl-24336862

RESUMO

Over 95% of all metazoan (animal) species comprise the "invertebrates," but very few genomes from these organisms have been sequenced. We have, therefore, formed a "Global Invertebrate Genomics Alliance" (GIGA). Our intent is to build a collaborative network of diverse scientists to tackle major challenges (e.g., species selection, sample collection and storage, sequence assembly, annotation, analytical tools) associated with genome/transcriptome sequencing across a large taxonomic spectrum. We aim to promote standards that will facilitate comparative approaches to invertebrate genomics and collaborations across the international scientific community. Candidate study taxa include species from Porifera, Ctenophora, Cnidaria, Placozoa, Mollusca, Arthropoda, Echinodermata, Annelida, Bryozoa, and Platyhelminthes, among others. GIGA will target 7000 noninsect/nonnematode species, with an emphasis on marine taxa because of the unrivaled phyletic diversity in the oceans. Priorities for selecting invertebrates for sequencing will include, but are not restricted to, their phylogenetic placement; relevance to organismal, ecological, and conservation research; and their importance to fisheries and human health. We highlight benefits of sequencing both whole genomes (DNA) and transcriptomes and also suggest policies for genomic-level data access and sharing based on transparency and inclusiveness. The GIGA Web site (http://giga.nova.edu) has been launched to facilitate this collaborative venture.


Assuntos
Genoma , Genômica/métodos , Invertebrados/classificação , Invertebrados/genética , Animais , Evolução Biológica , Organizações , Filogenia
13.
Amyloid ; 31(3): 184-194, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38801321

RESUMO

BACKGROUND: Numerous studies suggest a progressive accumulation of post-translationally modified peptides within amyloid fibrils, including isoaspartate (isoD) modifications. Here, we generated and characterised novel monoclonal antibodies targeting isoD-modified transthyretin (TTR). The antibodies were used to investigate the presence of isoD-modified TTR in deposits from transthyretin amyloidosis patients and to mediate antibody-dependent phagocytosis of TTR fibrils. METHODS: Monoclonal antibodies were generated by immunisation of mice using an isoD-modified peptide and subsequent hybridoma generation. The antibodies were characterised in terms of affinity and specificity to isoD-modified TTR using surface plasmon resonance, transmission electron microscopy and immunohistochemical staining of human cardiac tissue. The potential to elicit antibody-dependent phagocytosis of TTR fibrils was assessed using THP-1 cells. RESULTS: We developed two mouse monoclonal antibodies, 2F2 and 4D4, with high nanomolar affinity for isoD-modified TTR and strong selectivity over the unmodified epitope. Both antibodies show presence of isoD-modified TTR in human cardiac tissue, but not in freshly purified recombinant TTR, suggesting isoD modification only present in aged fibrillar deposits. Likewise, the antibodies only facilitated phagocytosis of TTR fibrils and not TTR monomers by THP-1 cells. CONCLUSIONS: These antibodies label aged, non-native TTR deposits, leaving native TTR unattended and thereby potentially enabling new therapeutic approaches.


Assuntos
Neuropatias Amiloides Familiares , Anticorpos Monoclonais , Imunoterapia , Pré-Albumina , Pré-Albumina/imunologia , Pré-Albumina/metabolismo , Pré-Albumina/química , Humanos , Animais , Neuropatias Amiloides Familiares/imunologia , Neuropatias Amiloides Familiares/patologia , Neuropatias Amiloides Familiares/metabolismo , Neuropatias Amiloides Familiares/terapia , Camundongos , Anticorpos Monoclonais/imunologia , Imunoterapia/métodos , Amiloide/metabolismo , Amiloide/imunologia , Fagocitose/imunologia , Células THP-1 , Feminino , Processamento de Proteína Pós-Traducional
14.
Mol Pharmacol ; 83(2): 542-51, 2013 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-23220749

RESUMO

Apomorphine is a non-narcotic derivative of morphine, which acts as a dopamine agonist and is clinically used to treat "off-states" in patients suffering from Parkinson's disease. Adverse effects of apomorphine treatment include severe emesis and nausea, and ulceration and pain at the injection site. We wanted to test whether sensory transient receptor potential (TRP) channels are a molecular target for apomorphine. Here, we show that rTRPV1, rTRPV2, rTRPV3, and mTRPV4, as well as hTRPM8, and rTRPM3, which are expressed in dorsal root ganglion neurons, are insensitive toward apomorphine treatment. This also applied to the cellular redox sensor hTRPM2. On the contrary, human TRPA1 could be concentration-dependently modulated by apomorphine. Whereas the addition of apomorphine in the low micromolar range produced an irreversible activation of the channel, application of higher concentrations caused a reversible voltage-dependent inhibition of heterologously expressed TRPA1 channels, resulting from a reduction of single-channel open times. In addition, we provide evidence that apomorphine also acts on endogenous TRPA1 in cultured dorsal root ganglion neurons from rats and in the enterochromaffin model cell line QGP-1, from which serotonin is released upon activation of TRPA1. Our study shows that human TRPA1 is a target for apomorphine, suggesting that an activation of TRPA1 might contribute to adverse side effects such as nausea and painful injections, which can occur during treatment with apomorphine.


Assuntos
Apomorfina/farmacologia , Canais de Potencial de Receptor Transitório/metabolismo , Animais , Cálcio/metabolismo , Linhagem Celular , Feminino , Gânglios Espinais/efeitos dos fármacos , Gânglios Espinais/metabolismo , Células HEK293 , Humanos , Masculino , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Ratos , Ratos Wistar , Serotonina/metabolismo
15.
Proc Biol Sci ; 280(1770): 20131876, 2013 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-24026823

RESUMO

Since its description from the Galapagos Rift in the mid-1980s, Archinome rosacea has been recorded at hydrothermal vents in the Pacific, Atlantic and Indian Oceans. Only recently was a second species described from the Pacific Antarctic Ridge. We inferred the identities and evolutionary relationships of Archinome representatives sampled from across the hydrothermal vent range of the genus, which is now extended to cold methane seeps. Species delimitation using mitochondrial cytochrome c oxidase subunit I (COI) recovered up to six lineages, whereas concatenated datasets (COI, 16S, 28S and ITS1) supported only four or five of these as clades. Morphological approaches alone were inconclusive to verify the identities of species owing to the lack of discrete diagnostic characters. We recognize five Archinome species, with three that are new to science. The new species, designated based on molecular evidence alone, include: Archinome levinae n. sp., which occurs at both vents and seeps in the east Pacific, Archinome tethyana n. sp., which inhabits Atlantic vents and Archinome jasoni n. sp., also present in the Atlantic, and whose distribution extends to the Indian and southwest Pacific Oceans. Biogeographic connections between vents and seeps are highlighted, as are potential evolutionary links among populations from vent fields located in the east Pacific and Atlantic Oceans, and Atlantic and Indian Oceans; the latter presented for the first time.


Assuntos
DNA Mitocondrial/genética , Filogenia , Poliquetos/classificação , Poliquetos/fisiologia , Animais , DNA Intergênico/genética , DNA Intergênico/metabolismo , DNA Mitocondrial/metabolismo , Ecossistema , Complexo IV da Cadeia de Transporte de Elétrons/genética , Complexo IV da Cadeia de Transporte de Elétrons/metabolismo , Fontes Hidrotermais , Dados de Sequência Molecular , Poliquetos/anatomia & histologia , Poliquetos/genética , RNA Ribossômico/genética , RNA Ribossômico/metabolismo , Análise de Sequência de DNA
16.
Mol Ecol ; 22(8): 2280-91, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23517352

RESUMO

Over the last few decades, advances in molecular techniques have led to the detection of strong geographic population structure and cryptic speciation in many benthic marine taxa, even those with long-lived pelagic larval stages. Polychaete annelids, in particular, generally show a high degree of population divergence, especially in mitochondrial genes. Rarely have molecular studies confirmed the presence of 'cosmopolitan' species. The amphinomid polychaete Hermodice carunculata was long considered the sole species within its genus, with a reported distribution throughout the Atlantic and adjacent basins. However, recent studies have indicated morphological differences, primarily in the number of branchial filaments, between the East and West Atlantic populations; these differences were invoked to re-instate Hermodice nigrolineata, formerly considered a junior synonym of H. carunculata. We utilized sequence data from two mitochondrial (cytochrome c oxidase subunit I, 16S rDNA) markers and one nuclear (internal transcribed spacer) marker to examine the genetic diversity of Hermodice throughout its distribution range in the Atlantic Ocean, including the Mediterranean Sea, the Caribbean Sea, the Gulf of Mexico and the Gulf of Guinea. Our analyses revealed generally low genetic divergences among collecting localities and between the East and West Atlantic, although phylogenetic trees based on mitochondrial data indicate the presence of a private lineage in the Mediterranean Sea. A re-evaluation of the number of branchial filaments confirmed differences between East and West Atlantic populations; however, the differences were not diagnostic and did not reflect the observed genetic population structure. Rather, we suspect that the number of branchial filaments is a function of oxygen saturation in the environment. Our results do not support the distinction between H. carunculata in the West Atlantic and H. nigrolineata in the East Atlantic. Instead, they re-affirm the older notion that H. carunculata is a cohesive species with a broad distribution across the Atlantic Ocean.


Assuntos
DNA Mitocondrial/genética , Variação Genética , Poliquetos/genética , RNA Ribossômico 16S/genética , Animais , Oceano Atlântico , Evolução Molecular , Dados de Sequência Molecular , Filogenia , Análise de Sequência de DNA , Especificidade da Espécie
17.
Biomolecules ; 12(7)2022 07 20.
Artigo em Inglês | MEDLINE | ID: mdl-35883562

RESUMO

The deposition of ß-amyloid peptides and of α-synuclein proteins is a neuropathological hallmark in the brains of Alzheimer's disease (AD) and Parkinson's disease (PD) subjects, respectively. However, there is accumulative evidence that both proteins are not exclusive for their clinical entity but instead co-exist and interact with each other. Here, we investigated the presence of a newly identified, pyroglutamate79-modified α-synuclein variant (pGlu79-aSyn)-along with the enzyme matrix metalloproteinase-3 (MMP-3) and glutaminyl cyclase (QC) implicated in its formation-in AD and in the transgenic Tg2576 AD mouse model. In the human brain, pGlu79-aSyn was detected in cortical pyramidal neurons, with more distinct labeling in AD compared to control brain tissue. Using immunohistochemical double and triple labelings and confocal laser scanning microscopy, we demonstrate an association of pGlu79-aSyn, MMP-3 and QC with ß-amyloid plaques. In addition, pGlu79-aSyn and QC were present in amyloid plaque-associated reactive astrocytes that were also immunoreactive for the chaperone heat shock protein 27 (HSP27). Our data are consistent for the transgenic mouse model and the human clinical condition. We conclude that pGlu79-aSyn can be generated extracellularly or within reactive astrocytes, accumulates in proximity to ß-amyloid plaques and induces an astrocytic protein unfolding mechanism involving HSP27.


Assuntos
Doença de Alzheimer , Doença de Alzheimer/metabolismo , Peptídeos beta-Amiloides/metabolismo , Animais , Encéfalo/metabolismo , Modelos Animais de Doenças , Proteínas de Choque Térmico HSP27/metabolismo , Humanos , Metaloproteinase 3 da Matriz/metabolismo , Camundongos , Camundongos Transgênicos , Placa Amiloide/metabolismo , Placa Amiloide/patologia , alfa-Sinucleína/genética , alfa-Sinucleína/metabolismo
18.
Behav Brain Res ; 434: 114020, 2022 09 26.
Artigo em Inglês | MEDLINE | ID: mdl-35870616

RESUMO

α-Synuclein (aSyn) is a protein implicated in physiological functions such as neurotransmitter release at the synapse and the regulation of gene expression in the nucleus. In addition, pathological aSyn assemblies are characteristic for a class of protein aggregation disorders referred to as synucleinopathies, where aSyn aggregates appear as Lewy bodies and Lewy neurites or as glial cytoplasmic inclusions. We recently discovered a novel post-translational pyroglutamate (pGlu) modification at Gln79 of N-truncated aSyn that promotes oligomer formation and neurotoxicity in human synucleinopathies. A priori, the appearance of pGlu79-aSyn in vivo involves a two-step process of free N-terminal Gln79 residue generation and subsequent cyclization of Gln79 into pGlu79. Prime candidate enzymes for these processes are matrix metalloproteinase-3 (MMP-3) and glutaminyl cyclase (QC). Here, we analyzed the expression of aSyn, MMP-3, QC and pGlu79-aSyn in brains of two transgenic mouse models for synucleinopathies (BAC-SNCA and ASO) by triple immunofluorescent labellings and confocal laser scanning microscopy. We report a co-localization of these proteins in brain structures typically affected by aSyn pathology, namely hippocampus in BAC-SNCA mice and substantia nigra in ASO mice. In addition, Western blot analyses revealed a high abundance of QC, MMP-3 and transgenic human aSyn in brain stem and thalamus but lower levels in cortex/hippocampus, whereas endogenous mouse aSyn was found to be most abundant in cortex/hippocampus, followed by thalamus and brain stem. During aging of ASO mice, we observed no differences between controls and transgenic mice in MMP-3 levels but higher QC content in thalamus of 6-month-old transgenic mice. Transgenic human aSyn abundance transiently increased and then showed decrease in oldest ASO mice analyzed. Immunohistochemistry revealed a successive increase in intraneuronal and extracellular formation of pGlu79-aSyn in substantia nigra during aging of ASO mice. Together, our data are supportive for a role of MMP-3 and QC in the generation of pGlu79-aSyn in brains affected by aSyn pathology.


Assuntos
Sinucleinopatias , alfa-Sinucleína , Animais , Encéfalo , Humanos , Lactente , Metaloproteinase 3 da Matriz , Camundongos , Camundongos Transgênicos
19.
Zookeys ; 1020: 1-198, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33708002

RESUMO

In Australia, the deep-water (bathyal and abyssal) benthic invertebrate fauna is poorly known in comparison with that of shallow (subtidal and shelf) habitats. Benthic fauna from the deep eastern Australian margin was sampled systematically for the first time during 2017 RV 'Investigator' voyage 'Sampling the Abyss'. Box core, Brenke sledge, and beam trawl samples were collected at one-degree intervals from Tasmania, 42°S, to southern Queensland, 24°S, from 900 to 4800 m depth. Annelids collected were identified by taxonomic experts on individual families around the world. A complete list of all identified species is presented, accompanied with brief morphological diagnoses, taxonomic remarks, and colour images. A total of more than 6000 annelid specimens consisting of 50 families (47 Polychaeta, one Echiura, two Sipuncula) and 214 species were recovered. Twenty-seven species were given valid names, 45 were assigned the qualifier cf., 87 the qualifier sp., and 55 species were considered new to science. Geographical ranges of 16 morphospecies extended along the eastern Australian margin to the Great Australian Bight, South Australia; however, these ranges need to be confirmed with genetic data. This work providing critical baseline biodiversity data on an important group of benthic invertebrates from a virtually unknown region of the world's ocean will act as a springboard for future taxonomic and biogeographic studies in the area.

20.
J Comp Physiol B ; 190(6): 681-689, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32960287

RESUMO

Oxygen is necessary for all marine animals to support metabolic functions. When chronic low dissolved oxygen (DO) conditions occur, organisms must adjust to overcome this stressor's effect on metabolic rates. The bearded fireworm, Hermodice carunculata, is a widespread species frequently exposed to hypoxic conditions in areas within its broad distribution which may impact metabolism, wound healing, and regeneration. To study the impact of hypoxia on their metabolic rates, we exposed fireworms to two levels of lower than normal DO conditions (low 2.5 ± 0.25 mg O2 L-1 and mid 4.5 ± 0.25 mg O2 L-1) for 7 days by pumping nitrogen into their holding tanks. During a chronic hypoxia trial, we quantified oxygen consumption in each experimental group and subsequently determined post-hypoxia oxygen consumption of individuals from the lowest oxygen level. During the hypoxic exposure, the oxygen uptake rates declined in low and mid DO conditions, while remaining relatively constant for the normoxic (7.0 ± 0.25 mg O2 L-1) control. We then compared the oxygen consumption rates from the lowest DO condition to fireworms likely never exposed to hypoxia and fireworms from a location likely to be exposed to hypoxia. We found higher oxygen consumption rates in the experimentally hypoxia-exposed worms. These results suggest prolonged negative impacts of hypoxic exposure, leading to a lasting elevation of metabolic rates of these marine invertebrates. The increase in metabolic rates may lead to increased predation on their prey of choice, economically and commercially important coral, causing increased degradation of already threatened coral reef ecosystems.


Assuntos
Anelídeos/metabolismo , Consumo de Oxigênio , Oxigênio/análise , Animais
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