RESUMO
A novel protein tyrosine kinase (PTK) substrate, p120, has been previously implicated in ligand-induced signaling through the epidermal growth factor, platelet-derived growth factor and colony-stimulating factor 1 receptors, and in cell transformation by p60v-src. We have isolated a near full-length cDNA encoding murine p120. The encoded protein lacks significant homology with any reported protein, but it contains four copies of an imperfect 42 amino acid repeat that occurs 12.5 times in the protein encoded by Drosophila armadillo (arm), and its direct homologs, human plakoglobin (plak) and Xenopus laevis beta-catenin (beta-cat). The presence of this motif implies that p120 may share at least one aspect of its function with the arm protein and its homologs.
Assuntos
Caderinas/genética , Moléculas de Adesão Celular/genética , Proteínas do Citoesqueleto/genética , DNA/genética , Proteínas de Drosophila , Proteína Oncogênica pp60(v-src)/metabolismo , Fosfoproteínas/genética , Fosfoproteínas/metabolismo , Proteínas Tirosina Quinases/metabolismo , Proteínas/genética , Receptores de Superfície Celular/metabolismo , Transativadores , Células 3T3 , Sequência de Aminoácidos , Animais , Proteínas do Domínio Armadillo , Sequência de Bases , Clonagem Molecular , DNA/isolamento & purificação , Sondas de DNA , Desmoplaquinas , Drosophila/genética , Biblioteca Gênica , Humanos , Hormônios de Inseto/genética , Camundongos , Dados de Sequência Molecular , Fosfoproteínas/isolamento & purificação , Reação em Cadeia da Polimerase/métodos , Homologia de Sequência de Aminoácidos , Homologia de Sequência do Ácido Nucleico , Especificidade por Substrato , Fatores de Transcrição , Xenopus , Proteínas de Xenopus , beta Catenina , gama CateninaRESUMO
A rare state of acquired hypercoagulability known as heparin-associated or heparin-induced thrombocytopenia and thrombosis (HATT, HITT) exists. It appears to be caused by an antibody reaction with heparin-platelet factor 4 complexes. A mild and severe form exist, but both varieties occur after exposure to heparin. The authors describe a fatal neonatal case of hypercoagulability on extracorporeal membrane oxygenation, and their evaluation that determined the etiology as type II HATT. They discuss the pathophysiology of HATT as well as possible alternative anticoagulation approaches.
Assuntos
Anticoagulantes/efeitos adversos , Trombose Coronária/induzido quimicamente , Oxigenação por Membrana Extracorpórea/efeitos adversos , Heparina/efeitos adversos , Trombocitopenia/induzido quimicamente , Evolução Fatal , Humanos , Recém-Nascido , MasculinoRESUMO
Pathways previously proposed for sensory transduction in chemotaxis to oxygen (aerotaxis) involved either (i) cytochrome o, the electron transport system, and proton motive force or (ii) enzyme IIGlucose and the phosphoenolpyruvate:carbohydrate phosphotransferase system for active transport. This investigation distinguished between these possibilities. Aerotaxis was absent in a cyo cyd strain of Escherichia coli that lacked both cytochrome o and cytochrome d, which are the terminal oxidases for the branched electron transport system in E. coli. Aerotaxis, measured by either a spatial or temporal assay, was normal in E. coli strains that had a cyo+ or cyd+ gene or both. The membrane potential of all oxidase-positive strains was approximately -170 mV in aerated medium at pH 7.5. Behavioral responses to changes in oxygen concentration correlated with changes in proton motive force. Aerotaxis was normal in ptsG and ptsI strains that lack enzyme IIGlucose and enzyme I, respectively, and are deficient in the phosphotransferase system. A cya strain that is deficient in adenylate cyclase also had normal aerotaxis. We concluded that aerotaxis was mediated by the electron transport system and that either the cytochrome d or the cytochrome o branch of the pathway could mediate aerotaxis.