Navegando por Assunto "Genoma mitocondrial"

Agora exibindo 1 - 2 de 2

Acesso aberto (Open Access)
Análise e caracterização do genoma mitocondrial: um estudo de caso de Cyprinodon sp. e Arapaima gigas
(Universidade Federal do Pará, 2025-05) MACEDO, Daralyns Borges; RAMOS, Rommel Thiago Juca; http://lattes.cnpq.br/1274395392752454; https://orcid.org/0000-0002-8032-1474
The advancement of next-generation sequencing technologies has enabled large-scale characterization of mitochondrial genomes across various species. However, even among fish — the group with the highest number of sequenced mitochondrial genomes — only 9.7% of valid species are represented in genetic databases. This gap limits conservation programs, which rely on genetic data to guide management strategies. The genus Cyprinodon, composed of several threatened species restricted to isolated habitats, is particularly vulnerable to habitat loss and interspecific hybridization. In this context, the present study aimed to sequence and characterize the mitochondrial genome of Cyprinodon sp., in order to clarify phylogenetic relationships and evolutionary aspects of the Cyprinodontidae family. The sample was sequenced using the Illumina HiSeq platform, assembled with Megahit software, and analyzed using tools such as MitoZ, Circos, ClustalW, MrBayes, and Figtree. The complete mitogenome comprises 16,500 bp and contains 37 genes. Concurrently, Arapaima gigas, an iconic Amazonian species historically important to fisheries, is currently threatened with extinction and classified as “Data Deficient” by the IUCN. In the Tocantins River, heavily impacted by human activities, fishers from 25 communities reported the near disappearance of the species, with only one recent sighting on Jaracuera Island. The disappearance of A. gigas has severe economic consequences for local communities. Without collaboration between fishery managers and local populations, the species faces an imminent risk of regional extinction, further exacerbated by the lack of data on its fishing dynamics in northern Brazil.
Acesso aberto (Open Access)
Avaliação da integridade genômica mitocondrial em gliomas de alto e baixo grau na população paraense
(Universidade Federal do Pará, 2016-12-14) COSTA JÚNIOR, Carlos Antonio da; BORGES, Bárbara do Nascimento; http://lattes.cnpq.br/0676220027193876
Cancer is characterized by fast abnormal cells proliferation which grow beyond their normal limits and may invade adjacent or distant tissue. Cancer CNS represents 2% of all cancers in the world, being slightly higher in men than in women. Mitochondria are responsible for producing most of the cellular ATP by oxidative phosphorylation (OXPHOS), may also act through glycolysis for same purpose, not requiring only oxygen. This option is a particular cancer cell property, also known as the Warburg effect. One hypothesis to explain this metabolic change may be related to mitochondrial DNA (mtDNA) defects caused by OXPHOS where these mutations can lead cancer cells to glycolysis. Eight mtDNA regions (D-LOOP, ND1, ND3, CO I, CO II CO III, ATPase 6 and ATPase 8) were analyzed in patients’ neoplastic tissues with glial cell cancer in Pará population, relating the data with the pathological and clinical characteristics of the patients. Among the changes found, the complex I seem to be decisive for the progression of high-grade tumors, as well as changes indel seem compromising important structures for OXPHOS. Deletions 4977 bp, when combined with other changes in ND1 / ND3 or heteroplasmias suggest poor prognosis, however, seem to have a reduced risk when changes in ND1 and ND3 are simultaneous.