Navegando por Palavras-chave "Mitochondrial"
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- ItemAcesso aberto (Open Access)Análise evolutiva do genoma mitocondrial de leveduras : perda do complexo I(Universidade Federal de São Paulo (UNIFESP), 2017-12-20) Lopes, Luciano Rodrigo [UNIFESP]; Briones, Marcelo Ribeiro da Silva [UNIFESP]; http://lattes.cnpq.br/0018992452321910; http://lattes.cnpq.br/5658864413425739; Universidade Federal de São Paulo (UNIFESP)The evolution of mitochondrial genomes is essential for the adaptation of yeasts to the variation of environmental levels of oxygen. Although Saccharomyces cerevisiae mitochondrial DNA lacks all complex I genes, respiration is possible because alternative NADH dehydrogenases are encoded by NDE1 and NDI1 nuclear genes. The proposed whole genome duplication (WGD) in the yeast ancestor at 150-100 million years ago caused nuclear gene duplications and secondary losses, although its relation to the loss of complex I mitocondrial is unknown. Here we present phylogenomic supertrees and supermatix tree of 46 mitochondrial genomes showing that the loss of complex I predates WGD and occurred independently in the Saccharomyces cerevisiae group and the fission yeast Schizosaccharomyces pombe. We also showed that the pattern of branching trees did not deviate dramatically between supertrees and supermatrix phylogenetic tree. Phylogeny indicated consistent relations between conserved mitochondrial gene order with closely related yeast species. Correlation of the mitochondrial genes based molecular clock estimatives with variations of atmospheric oxygen concentrations data in the Phanerozoic suggests that the Saccharomyces lineage might have lost the complex I during hypoxic periods near Perminian-Triassic or Triassic-Jurassic mass extinction events. While Schizosaccharomyces lineage possibly lost the complex I during hypoxic environment periods during Middle Cambrian until Lower Devonian, a long period under hipoxya. Loss of mitochondrial complex I during low offering oxygen might not improved yeast metabolism. However, the return to increased oxygen environment periods might to pressed alternative adaptations from respiratory process. Thus, we also showed that NDE1 and NDI1 based phylogenies suggest evolutionary convergence in yeasts where mitochondrial complex I is absent.
- ItemAcesso aberto (Open Access)Avaliação audiológica na doença mitocondrial: relato de dois casos(CEFAC Saúde e Educação, 2008-12-01) Silveira, Marcela Rosana Maia da [UNIFESP]; Gil, Daniela [UNIFESP]; Universidade Federal de São Paulo (UNIFESP)BACKGROUND: hearing and mitochondriopathy. PROCEDURE: this case report aims at describing audiological evaluation results of two children diagnosed with mitochondrial disease referred to Clinical Audiology Out-patient Clinic of UNIFESP/EPM. Children were referred to audiology department from metabolic diseases out-patient clinic of UNIFESP. Both have undergone pure tone audiometry, behavioral observation, immittance measures and otoacoustic emissions. RESULTS: either behavioral or physiological evaluations revealed abnormal results evidencing mild to moderate-to-severe sensorineural hearing loss and presence of startle reflex without habituation, indicating central auditory involvement. CONCLUSION: these case reports reinforce the importance of considering the association of risk factor for hearing loss in the rehabilitation planning of these patients.
- ItemAcesso aberto (Open Access)Phenotypic spectrum of FARS2-deficiency(Elsevier Science Bv, 2018) Finsterer, Josef; Scorza, Carla Alessandra [UNIFESP]; Scorza, Fulvio Alexandre [UNIFESP]