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1.
CMAJ ; 195(40): E1364-E1379, 2023 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-37844924

RESUMO

BACKGROUND: In Canada, low awareness of evidence-based interventions for the clinical management of alcohol use disorder exists among health care providers and people who could benefit from care. To address this gap, the Canadian Research Initiative in Substance Misuse convened a national committee to develop a guideline for the clinical management of high-risk drinking and alcohol use disorder. METHODS: Development of this guideline followed the ADAPTE process, building upon the 2019 British Columbia provincial guideline for alcohol use disorder. A national guideline committee (consisting of 36 members with diverse expertise, including academics, clinicians, people with lived and living experiences of alcohol use, and people who self-identified as Indigenous or Métis) selected priority topics, reviewed evidence and reached consensus on the recommendations. We used the Appraisal of Guidelines for Research and Evaluation Instrument (AGREE II) and the Guidelines International Network's Principles for Disclosure of Interests and Management of Conflicts to ensure the guideline met international standards for transparency, high quality and methodological rigour. We rated the final recommendations using the Grading of Recommendations, Assessment, Development and Evaluation (GRADE) tool; the recommendations underwent external review by 13 national and international experts and stakeholders. RECOMMENDATIONS: The guideline includes 15 recommendations that cover screening, diagnosis, withdrawal management and ongoing treatment, including psychosocial treatment interventions, pharmacotherapies and community-based programs. The guideline committee identified a need to emphasize both underused interventions that may be beneficial and common prescribing and other practice patterns that are not evidence based and that may potentially worsen alcohol use outcomes. INTERPRETATION: The guideline is intended to be a resource for physicians, policymakers and other clinical and nonclinical personnel, as well as individuals, families and communities affected by alcohol use. The recommendations seek to provide a framework for addressing a large burden of unmet treatment and care needs for alcohol use disorder within Canada in an evidence-based manner.


Assuntos
Alcoolismo , Humanos , Alcoolismo/diagnóstico , Alcoolismo/terapia , Consumo de Bebidas Alcoólicas/terapia , Colúmbia Britânica
2.
Mov Disord ; 36(6): 1362-1371, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33836114

RESUMO

BACKGROUND: A common genetic mutation that causes Parkinson's disease (PD) is the G2019S LRRK2 mutation. A precision medicine approach that selectively blocks only excess kinase activity of the mutant allele could yield a safe and effective treatment for G2019S LRRK2 PD. OBJECTIVE: To determine the activity of a G2019S mutant selective leucine-rich repeat kinase 2 (LRRK2) kinase inhibitor as compared to a nonselective inhibitor in blood of subjects with genetic and idiopathic PD on two LRRK2 biomarkers, pSer935 LRRK2 and pThr73 Rab10. METHODS: Blood was collected from 13 subjects with or without a G2019S LRRK2 mutation with PD and one healthy control. Peripheral blood mononuclear cells were treated ex vivo with a novel G2019S LRRK2 inhibitor (EB-42168) or the nonselective inhibitor MLi-2. Quantitative western immunoblot analyses were performed. RESULTS: EB-42168 was 100 times more selective for G2019S LRRK2 when compared to wild-type (WT) LRRK2. Concentrations that inhibited phosphorylation of pSer935 LRRK2 by 90% in homozygous G2019S LRRK2 patients, inhibited pSer935 LRRK2 by 36% in heterozygous patients, and by only 5% in patients carrying only the WT allele. Similar selectivity was seen for pThr73 Rab10. MLi-2 showed an equivalent level of inhibition across all genotypes. CONCLUSIONS: These findings demonstrate that EB-42168, a G2019S LRRK2 selective inhibitor, lowers mutant G2019S LRRK2 phosphorylated biomarkers while simultaneously sparing WT LRRK2. Selective targeting of G2019S LRRK2 with a small molecule lays the foundation for a precision medicine treatment of G2019S LRRK2 PD. © 2021 ESCAPE Bio, Inc. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Doença de Parkinson , Heterozigoto , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Leucócitos Mononucleares , Mutação/genética , Doença de Parkinson/tratamento farmacológico , Doença de Parkinson/genética
3.
Int Arch Allergy Immunol ; 180(2): 91-102, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31401630

RESUMO

INTRODUCTION: Pathologic accumulation and activation of mast cells and eosinophils are implicated in allergic and inflammatory diseases. Sialic acid-binding immunoglobulin-like lectin (Siglec)-8 is an inhibitory receptor selectively expressed on mast cells, eosinophils and, at a lower extent, basophils. When engaged with an antibody, Siglec-8 can induce apoptosis of activated eosinophils and inhibit mast cell activation. AK002 is a humanized, non-fucosylated IgG1 anti-Siglec-8 antibody undergoing clinical investigation for treatment of allergic, inflammatory, and proliferative diseases. Here we examine the human tissue selectivity of AK002 and evaluate the in vitro, ex vivo, and in vivo activity of AK002 on eosinophils and mast cells. METHODS: The affinity of AK002 for Siglec-8 and CD16 was determined by biolayer interferometry. Ex vivo activity of AK002 on human eosinophils from blood and dissociated human tissue was tested in apoptosis and antibody-dependent cell-mediated cytotoxicity (ADCC) assays. The in vivo activity of a murine precursor of AK002 (mAK002) was tested in a passive systemic anaphylaxis (PSA) humanized mouse model. RESULTS: AK002 bound selectively to mast cells, eosinophils and, at a lower level, to basophils in human blood and tissue and not to other cell types examined. AK002 induced apoptosis of interleukin-5-activated blood eosinophils and demonstrated potent ADCC activity against blood eosinophils in the presence of natural killer cells. AK002 also significantly reduced eosinophils in dissociated human lung tissue. Furthermore, mAK002 prevented PSA in humanized mice through mast cell inhibition. CONCLUSION: AK002 selectively evokes potent apoptotic and ADCC activity against eosinophils and prevents systemic anaphylaxis through mast cell inhibition.


Assuntos
Anafilaxia/prevenção & controle , Anticorpos Monoclonais Humanizados/imunologia , Citotoxicidade Celular Dependente de Anticorpos/imunologia , Antígenos CD/imunologia , Antígenos de Diferenciação de Linfócitos B/imunologia , Eosinófilos/imunologia , Lectinas/imunologia , Mastócitos/imunologia , Anafilaxia/imunologia , Animais , Anticorpos Monoclonais Humanizados/uso terapêutico , Basófilos/imunologia , Humanos , Camundongos , Ácido N-Acetilneuramínico/imunologia , Receptores de IgG/imunologia
4.
CMAJ ; 196(9): E303-E321, 2024 Mar 10.
Artigo em Francês | MEDLINE | ID: mdl-38467412

RESUMO

CONTEXTE: Au Canada, on note que les équipes soignantes et les personnes qui bénéficieraient de soins ciblés connaissent peu les interventions fondées sur des données probantes pour la prise en charge clinique du trouble d'utilisation de l'alcool. Pour combler cette lacune, l'Initiative canadienne de recherche sur l'abus de substances a créé un comité national dans le but d'élaborer une ligne directrice pour la prise en charge clinique de la consommation d'alcool à risque élevé et du trouble lié à la consommation d'alcool. MÉTHODES: L'élaboration de cette ligne directrice s'est faite selon le processus ADAPTE, et est inspirée par une ligne directrice britanno-colombienne de 2019 pour le trouble lié à la consommation d'alcool. Un comité national de rédaction de la ligne directrice (composé de 36 membres de divers horizons, notamment des universitaires, des médecins, des personnes ayant ou ayant eu des expériences de consommation d'alcool et des personnes s'identifiant comme Autochtones ou Métis) a choisi les thèmes prioritaires, a passé en revue les données probantes et atteint un consensus relatif aux recommandations. Nous avons utilisé l'outil AGREE II (Appraisal of Guidelines for Research and Evaluation Instrument II) et les principes de divulgation des intérêts et de gestion des conflits lors du processus de rédaction des lignes directrices (Principles for Disclosure of Interests and Management of Conflicts in Guidelines) publiés en anglais par le Réseau international des lignes directrices (Guidelines International Network) pour nous assurer que la ligne directrice répondait aux normes internationales de transparence, de qualité élevée et de rigueur méthodologique. Nous avons évalué les recommandations finales à l'aide de l'approche GRADE (Grading of Recommendations Assessment, Development, and Evaluation). Les recommandations ont fait l'objet d'une revue externe par 13 spécialistes et parties prenantes d'ici et de l'étranger. RECOMMANDATIONS: La ligne directrice comprend 15 recommandations qui concernent le dépistage, le diagnostic, la prise en charge du sevrage et le traitement continu, y compris les interventions psychosociales, les pharmacothérapies et les programmes communautaires. Le comité de rédaction de la ligne directrice a reconnu la nécessité d'insister sur la sous-utilisation des interventions qui pourraient être bénéfiques et sur les modes de prescription et autres pratiques d'usage courant qui ne reposent pas sur des données probantes et pourraient aggraver les effets de la consommation d'alcool. INTERPRÉTATION: La ligne directrice se veut une ressource à l'intention des médecins, des responsables des orientations politiques et des membres des équipes cliniques et autres, de même que des personnes, des familles et des communautés affectées par la consommation d'alcool. Ces recommandations proposent un cadre fondé sur des données probantes pour alléger le lourd fardeau du trouble d'utilisation de l'alcool au Canada et combler les besoins en matière de traitements et de soins.


Assuntos
Alcoolismo , Humanos , Canadá , Consumo de Bebidas Alcoólicas
5.
Mol Cell Neurosci ; 56: 355-64, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23891805

RESUMO

Development of therapeutics for genetically complex neurodegenerative diseases such as sporadic amyotrophic lateral sclerosis (ALS) has largely been hampered by lack of relevant disease models. Reprogramming of sporadic ALS patients' fibroblasts into induced pluripotent stem cells (iPSC) and differentiation into affected neurons that show a disease phenotype could provide a cellular model for disease mechanism studies and drug discovery. Here we report the reprogramming to pluripotency of fibroblasts from a large cohort of healthy controls and ALS patients and their differentiation into motor neurons. We demonstrate that motor neurons derived from three sALS patients show de novo TDP-43 aggregation and that the aggregates recapitulate pathology in postmortem tissue from one of the same patients from which the iPSC were derived. We configured a high-content chemical screen using the TDP-43 aggregate endpoint both in lower motor neurons and upper motor neuron like cells and identified FDA-approved small molecule modulators including Digoxin demonstrating the feasibility of patient-derived iPSC-based disease modeling for drug screening.


Assuntos
Esclerose Lateral Amiotrófica/patologia , Reprogramação Celular , Fibroblastos/citologia , Células-Tronco Pluripotentes Induzidas/citologia , Neurônios Motores/citologia , Esclerose Lateral Amiotrófica/metabolismo , Estudos de Casos e Controles , Diferenciação Celular , Proteínas de Ligação a DNA/genética , Proteínas de Ligação a DNA/metabolismo , Fibroblastos/metabolismo , Fibroblastos/patologia , Humanos , Células-Tronco Pluripotentes Induzidas/metabolismo , Células-Tronco Pluripotentes Induzidas/patologia , Neurônios Motores/metabolismo , Neurônios Motores/patologia
6.
Arthritis Rheum ; 62(8): 2303-12, 2010 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-20506554

RESUMO

OBJECTIVE: During the course of different musculoskeletal diseases, joints are progressively damaged by inflammatory, infectious, or mechanical stressors, leading to joint destruction and disability. While effective strategies to inhibit joint inflammation, such as targeted cytokine-blocking therapy, have been developed during the last decade, the molecular mechanisms of joint damage are still poorly understood. This study was undertaken to investigate the role of the Wnt pathway modulator R-Spondin 1 (RSpo1) in protecting bone and cartilage in a mouse model of arthritis. METHODS: Tumor necrosis factor alpha (TNFalpha)-transgenic mice were treated with vehicle or Rspo1. Mice were evaluated for signs of arthritis, and histologic analysis of the hind paws was performed. Moreover, we determined the effect of Rspo1 on Wnt signaling activity and osteoprotegerin (OPG) expression in murine primary osteoblasts. RESULTS: The secreted Wnt pathway modulator RSpo1 was highly effective in preserving the structural integrity of joints in a TNFalpha-transgenic mouse model of arthritis by protecting bone and cartilage from inflammation-related damage. RSpo1 antagonized the Wnt inhibitor Dkk-1 and modulated Wnt signaling in mouse mesenchymal cells. In osteoblasts, RSpo1 induced differentiation and expression of OPG, thereby inhibiting osteoclastogenesis in vitro. In vivo, RSpo1 promoted osteoblast differentiation and bone formation while blocking osteoclast development, thereby contributing to the integrity of joints during inflammatory arthritis. CONCLUSION: Our results demonstrate the therapeutic potential of RSpo1 as an anabolic agent for the preservation of joint architecture.


Assuntos
Artrite Experimental/metabolismo , Osso e Ossos/metabolismo , Cartilagem/metabolismo , Inflamação/metabolismo , Trombospondinas/metabolismo , Proteínas Wnt/metabolismo , Animais , Artrite Experimental/tratamento farmacológico , Artrite Experimental/patologia , Western Blotting , Osso e Ossos/efeitos dos fármacos , Osso e Ossos/patologia , Cartilagem/efeitos dos fármacos , Cartilagem/patologia , Imunofluorescência , Hibridização In Situ , Inflamação/tratamento farmacológico , Inflamação/patologia , Camundongos , Camundongos Transgênicos , Osteoblastos/efeitos dos fármacos , Osteoblastos/metabolismo , Osteoblastos/patologia , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Trombospondinas/farmacologia , Fator de Necrose Tumoral alfa/genética , Fator de Necrose Tumoral alfa/metabolismo
7.
J Med Chem ; 63(23): 14821-14839, 2020 12 10.
Artigo em Inglês | MEDLINE | ID: mdl-33197196

RESUMO

Pathogenic variants in the leucine-rich repeat kinase 2 (LRRK2) gene have been identified that increase the risk for developing Parkinson's disease in a dominantly inherited fashion. These pathogenic variants, of which G2019S is the most common, cause abnormally high kinase activity, and compounds that inhibit this activity are being pursued as potentially disease-modifying therapeutics. Because LRRK2 regulates important cellular processes, developing inhibitors that can selectively target the pathogenic variant while sparing normal LRRK2 activity could offer potential advantages in heterozygous carriers. We conducted a high-throughput screen and identified a single selective compound that preferentially inhibited G2019S-LRRK2. Optimization of this scaffold led to a series of novel, potent, and highly selective G2019S-LRRK2 inhibitors.


Assuntos
Indazóis/farmacologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/antagonistas & inibidores , Inibidores de Proteínas Quinases/farmacologia , Pirimidinas/farmacologia , Tetrazóis/farmacologia , Animais , Células HEK293 , Ensaios de Triagem em Larga Escala , Humanos , Indazóis/síntese química , Indazóis/farmacocinética , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Camundongos , Estrutura Molecular , Mutação , Inibidores de Proteínas Quinases/síntese química , Inibidores de Proteínas Quinases/farmacocinética , Pirimidinas/síntese química , Pirimidinas/farmacocinética , Bibliotecas de Moléculas Pequenas/síntese química , Bibliotecas de Moléculas Pequenas/farmacocinética , Bibliotecas de Moléculas Pequenas/farmacologia , Relação Estrutura-Atividade , Tetrazóis/síntese química , Tetrazóis/farmacocinética
8.
Exp Brain Res ; 191(3): 341-51, 2008 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-18712372

RESUMO

The pitch-shift reflex is a corrective voice fundamental frequency (F0) response triggered by a sudden shift or "error" in auditory feedback pitch. We investigated how anticipating a voice pitch error affects the pitch-shift reflex and volitional voice F0 responses. Adults sustained the vowel/u/at a comfortable pitch and pressed a button to deliver a 100 cent, 100 ms auditory feedback pitch shift immediately or after a random delay. Pitch shift direction was either constant (up) or randomized (up or down). Onset anticipation often resulted in an anticipatory voice F0 change, but stimulus direction predictability did not affect the responses. When pitch error onset and direction were both anticipated, some participants produced an ideomotor voice F0 change that partially imitated the error, but they produced no apparent pitch-shift reflex. Results imply that when voice pitch errors are anticipated, volitional voice F0 responses may reduce or enhance voice F0 stability.


Assuntos
Percepção da Altura Sonora/fisiologia , Reflexo/fisiologia , Voz/fisiologia , Volição/fisiologia , Estimulação Acústica , Adulto , Disfonia/fisiopatologia , Retroalimentação/fisiologia , Feminino , Humanos , Laringe/fisiologia , Masculino , Neurônios Motores/fisiologia , Tempo de Reação/fisiologia , Adulto Jovem
9.
Neurobiol Aging ; 36(2): 693-709, 2015 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-25442111

RESUMO

The interaction of amyloid-beta (Aß) and tau in the pathogenesis of Alzheimer's disease is a subject of intense inquiry, with the bulk of evidence indicating that changes in tau are downstream of Aß. It has been shown however, that human tau overexpression in amyloid precursor protein transgenic mice increases Aß plaque deposition. Here, we confirm that human tau increases Aß levels. To determine if the observed changes in Aß levels were because of intracellular or extracellular secreted tau (eTau for extracellular tau), we affinity purified secreted tau from Alzheimer's disease patient-derived cortical neuron conditioned media and analyzed it by liquid chromatography-mass spectrometry. We found the extracellular species to be composed predominantly of a series of N-terminal fragments of tau, with no evidence of C-terminal tau fragments. We characterized a subset of high affinity tau antibodies, each capable of engaging and neutralizing eTau. We found that neutralizing eTau reduces Aß levels in vitro in primary human cortical neurons where exogenously adding eTau increases Aß levels. In vivo, neutralizing human tau in 2 human tau transgenic models also reduced Aß levels. We show that the human tau insert sequence is sufficient to cause the observed increase in Aß levels. Our data furthermore suggest that neuronal hyperactivity may be the mechanism by which this regulation occurs. We show that neuronal hyperactivity regulates both eTau secretion and Aß production. Electrophysiological analysis shows for the first time that secreted eTau causes neuronal hyperactivity. Its induction of hyperactivity may be the mechanism by which eTau regulates Aß production. Together with previous findings, these data posit a novel connection between tau and Aß, suggesting a dynamic mechanism of positive feed forward regulation. Aß drives the disease pathway through tau, with eTau further increasing Aß levels, perpetuating a destructive cycle.


Assuntos
Peptídeos beta-Amiloides/metabolismo , Neurônios/metabolismo , Proteínas tau/fisiologia , Doença de Alzheimer/etiologia , Doença de Alzheimer/metabolismo , Animais , Células Cultivadas , Córtex Cerebral/citologia , Cromatografia Líquida , Humanos , Espectrometria de Massas , Camundongos Transgênicos , Neurônios/fisiologia , Proteínas tau/química , Proteínas tau/isolamento & purificação
10.
Mol Biol Cell ; 20(15): 3552-60, 2009 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-19477926

RESUMO

The Wnt coreceptor LRP6 is required for canonical Wnt signaling. To understand the molecular regulation of LRP6 function, we generated a series of monoclonal antibodies against the extra cellular domain (ECD) of LRP6 and selected a high-affinity mAb (mAb135) that recognizes cell surface expression of endogenous LRP6. mAb135 enhanced Wnt dependent TCF reporter activation and antagonized DKK1 dependent inhibition of Wnt3A signaling, suggesting a role in modulation of LRP6 function. Detailed analysis of LRP6 domain mutants identified Ser 243 in the first propeller domain of LRP6 as a critical residue for mAb135 binding, implicating this domain in regulating the sensitivity of LRP6 to DKK1. In agreement with this notion, mAb135 directly disrupted the interaction of DKK1 with recombinant ECD LRP6 and a truncated form of the LRP6 ECD containing only repeats 1 and 2. Finally, we found that mAb135 completely protected LRP6 from DKK1 dependent internalization. Together, these results identify the first propeller domain as a novel regulatory domain for DKK1 binding to LRP6 and show that mAb against the first propeller domain of LRP6 can be used to modulate this interaction.


Assuntos
Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Proteínas Relacionadas a Receptor de LDL/metabolismo , Anticorpos Monoclonais/imunologia , Anticorpos Monoclonais/farmacologia , Sítios de Ligação/genética , Sítios de Ligação/imunologia , Western Blotting , Linhagem Celular , Endocitose/efeitos dos fármacos , Citometria de Fluxo , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Proteínas Relacionadas a Receptor de LDL/genética , Proteínas Relacionadas a Receptor de LDL/imunologia , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Mutação , Ligação Proteica/efeitos dos fármacos , Interferência de RNA , Transdução de Sinais/efeitos dos fármacos , Proteínas Wnt/genética , Proteínas Wnt/metabolismo , Proteína Wnt3 , Proteína Wnt3A
11.
Proc Natl Acad Sci U S A ; 104(37): 14700-5, 2007 Sep 11.
Artigo em Inglês | MEDLINE | ID: mdl-17804805

RESUMO

The R-Spondin (RSpo) family of secreted proteins act as potent activators of the Wnt/beta-catenin signaling pathway. We have previously shown that RSpo proteins can induce proliferative effects on the gastrointestinal epithelium in mice. Here we provide a mechanism whereby RSpo1 regulates cellular responsiveness to Wnt ligands by modulating the cell-surface levels of the coreceptor LRP6. We show that RSpo1 activity critically depends on the presence of canonical Wnt ligands and LRP6. Although RSpo1 does not directly activate LRP6, it interferes with DKK1/Kremen-mediated internalization of LRP6 through an interaction with Kremen, resulting in increased LRP6 levels on the cell surface. Our results support a model in which RSpo1 relieves the inhibition DKK1 imposes on the Wnt pathway.


Assuntos
Proteínas Relacionadas a Receptor de LDL/antagonistas & inibidores , Transdução de Sinais , Trombospondinas/metabolismo , Proteínas Wnt/metabolismo , Animais , Linhagem Celular , Drosophila/citologia , Drosophila/metabolismo , Regulação da Expressão Gênica , Genes Reporter , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/genética , Peptídeos e Proteínas de Sinalização Intercelular/metabolismo , Rim/citologia , Proteínas Relacionadas a Receptor de LDL/metabolismo , Ligantes , Proteína-6 Relacionada a Receptor de Lipoproteína de Baixa Densidade , Luciferases/metabolismo , Proteínas de Membrana/metabolismo , Modelos Biológicos , Fosforilação , Testes de Precipitina , Ligação Proteica , RNA Interferente Pequeno/metabolismo , Proteínas Recombinantes/metabolismo , Trombospondinas/genética , Transfecção , beta Catenina/genética , beta Catenina/metabolismo
12.
J Mol Evol ; 61(3): 372-80, 2005 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-16044242

RESUMO

An emerging series of papers has identified new receptor proteins that predict seven-transmembrane pass topologies. We have consolidated this family to 11 human genes and have named the family PAQR, after two of the initially described ligands (progestin and adipoQ receptors). This protein family has ancient evolutionary roots, with identified homologs found in eubacteria. To date, published data indicate that the prokaryotic members of this family appear to encode hemolysin-type proteins, while in eukaryotes, PAQR proteins encode functional receptors with a broad range of apparent ligand specificities. We provide the complete human and mouse complement of this family, suggest a conserved structure/topology with invariant intracellular amino acid residues, and have measured mRNA expression levels for these genes across a range of human tissues.


Assuntos
Membrana Celular/metabolismo , Receptores de Superfície Celular/química , Receptores de Superfície Celular/classificação , Sequência de Aminoácidos , Animais , Evolução Molecular , Humanos , Camundongos , Dados de Sequência Molecular , Filogenia , RNA Mensageiro/análise , RNA Mensageiro/genética , Receptores de Superfície Celular/genética , Receptores de Superfície Celular/metabolismo , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
13.
Genomics ; 86(1): 100-11, 2005 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15953544

RESUMO

The C-terminal domains of the A, B, C chains of C1q subcomponent of C1 complex represent a common structural motif, the C1q domain, that is found in a diverse range of proteins. We analyzed the human genome for the complete complement of this family and have identified a total of 31 independent gene sequences. The predominant organization of C1q-domain-containing (C1qDC) proteins includes a leading signal peptide, a collagen-like region of variable length, and a C-terminal C1q domain. There are 15 highly conserved residues within the C1q domain, among which 8 are invariant within the human gene set and these are predicted to cluster within the hydrophobic core of the protein. We suggest a 3-subfamily classification based on sequence homology. For some C1qDC-encoding genes, strict orthology has been retained throughout vertebrate evolution and these examples suggest a highly specific functional role for C1qDC proteins that has been under significant selective pressure. Alternatively, individual species have co-opted C1qDC proteins for roles that are highly specific to their biology, suggesting an evolutionary strategy of gene duplication and functional diversification. A more extensive analysis of the evolutionary relationship of C1qDC proteins reveals an ancient rooting, with clear members found in eubacterial species. Curiously, we have been unable to identify C1qDC-encoding genes in many eukaryotic genomcs, such as Sacchromyces cerivisae and C. elegans, suggesting that the retention or loss of this gene family throughout evolution has been sporadic.


Assuntos
Complemento C1q/genética , Genoma Humano , Sequência de Aminoácidos , Animais , Complemento C1q/química , Bases de Dados de Proteínas , Evolução Molecular , Variação Genética , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Filogenia , Conformação Proteica , Alinhamento de Sequência , Homologia de Sequência de Aminoácidos
14.
Biochem Biophys Res Commun ; 315(2): 272-80, 2004 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-14766204

RESUMO

Drosophila Crossveinless-2 (dCV-2) is required for local activation of Mad phosphorylation in the fruit fly wing and has been postulated to be a positive regulator of BMP-mediated signaling. In contrast, the presence of 5 Chordin-like cysteine-rich domains in the CV-2 protein suggests that CV-2 belongs to a family of well-established inhibitors of BMP function that includes Chordin and Sog [Development 127 (2000) 3947]. We have identified a human homolog of Drosophila CV-2 (hCV-2). Here we show that purified recombinant hCV-2 protein inhibits BMP-2 and BMP-4 dependent osteogenic differentiation of W-20-17 cells, as well as BMP dependent chondrogenic differentiation of ATDC5 cells. Interestingly, hCV-2 messenger RNA is expressed at high levels in human primary chondrocytes, whereas expression in primary human osteoblasts is low. These results suggest that hCV-2 may regulate BMP responsiveness of osteoblasts and chondrocytes in vivo. Taken together we have shown that contrary to the function predicted from the fruit fly, Crossveinless-2 is a novel inhibitor of BMP function.


Assuntos
Proteínas Morfogenéticas Ósseas/antagonistas & inibidores , Proteínas de Drosophila/fisiologia , Fator de Crescimento Transformador beta , Fosfatase Alcalina/metabolismo , Animais , Proteína Morfogenética Óssea 2 , Proteína Morfogenética Óssea 4 , Proteínas Morfogenéticas Ósseas/metabolismo , Diferenciação Celular , Divisão Celular , Linhagem Celular , Células Cultivadas , Cisteína/química , DNA Complementar/metabolismo , Relação Dose-Resposta a Droga , Drosophila , Proteínas de Drosophila/metabolismo , Glicoproteínas/química , Humanos , Peptídeos e Proteínas de Sinalização Intercelular/química , Camundongos , Osteoblastos/metabolismo , Fenótipo , Fosforilação , Estrutura Terciária de Proteína , RNA Mensageiro/metabolismo , Proteínas Recombinantes/química , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Transdução de Sinais , Distribuição Tecidual
15.
Immunogenetics ; 54(5): 293-300, 2002 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-12185532

RESUMO

We have identified three novel, rarely expressed human genes that encode new members of the lipid transfer/lipopolysaccharide binding protein (LT/LBP) gene family based on sequence homology. BPI and other members of the LT/LBP family are structurally related proteins capable of binding phospholipids and lipopolysaccharides. Real-time PCR studies indicate that BPIL1 and BPIL3 are highly expressed in hypertrophic tonsils. In situ hybridization analysis of BPIL2 shows prominent expression in skin specimens from psoriasis patients. BPIL1 and BPIL3 map to Chromosome 20q11; thus, these novel genes form a cluster with BPI and two other members of the LT/LBP gene family on the long arm of human Chr 20. BPIL2maps to Chr 22q13. The exon/intron organization of all three genes is highly conserved with that of BPI, suggesting evolution from a common ancestor.


Assuntos
Proteínas de Transporte/genética , Cromossomos Humanos Par 20/genética , Cromossomos Humanos Par 22/genética , Família Multigênica , Sequência de Aminoácidos , Proteínas de Transporte/biossíntese , Proteínas de Transporte/química , Proteínas de Transporte/fisiologia , Mapeamento Cromossômico , Clonagem Molecular , Sistemas Computacionais , DNA Complementar/genética , Evolução Molecular , Perfilação da Expressão Gênica , Humanos , Modelos Moleculares , Dados de Sequência Molecular , Especificidade de Órgãos , Reação em Cadeia da Polimerase/métodos , Conformação Proteica
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