Heterotrophic protists are vital in Earth's ecosystems, influencing carbon and nutrient cycles and occupying key positions in food webs as microbial predators. Fossils and molecular data suggest the emergence of predatory microeukaryotes and the transition to a eukaryote-rich marine environment by 800 million years ago (Ma). Neoproterozoic vase-shaped microfossils (VSMs) linked to Arcellinida testate amoebae represent the oldest evidence of heterotrophic microeukaryotes.
View Article and Find Full Text PDFArcellinida is ascending in importance in protistology, but description of their diversity still presents multiple challenges. Furthermore, applicable tools for surveillance of these organisms are still in developing stages. Importantly, a good database that sets a correspondence between molecular barcodes and species morphology is lacking.
View Article and Find Full Text PDFMol Phylogenet Evol
October 2022
Protists, the micro-eukaryotes that are neither plants, animals nor fungi build up the greatest part of eukaryotic diversity on Earth. Yet, their evolutionary histories and patterns are still mostly ignored, and their complexity overlooked. Protists are often assumed to keep stable morphologies for long periods of time (morphological stasis).
View Article and Find Full Text PDFArsenic is a ubiquitous element in the environment, a source of constant evolutionary pressure on organisms. The arsenic resistance machinery is thoroughly described for bacteria. Highly resistant lineages are also common in eukaryotes, but evolutionary knowledge is much more limited.
View Article and Find Full Text PDFBackground: Peripheral arterial disease (PAD) affects millions of people and compromises quality of life. Critical limb ischemia (CLI), which is the most advanced stage of PAD, can cause nonhealing ulcers and strong chronic pain, and it shortens the patients' life expectancy. Cell-based angiogenic therapies are becoming a real therapeutic approach to treat CLI.
View Article and Find Full Text PDFThe distribution pattern of the meiotic machinery in known eukaryotes is most parsimoniously explained by the hypothesis that all eukaryotes are ancestrally sexual. However, this assumption is questioned by preliminary results, in culture conditions. These suggested that Acanthamoeba, an organism considered to be largely asexual, constitutively expresses meiosis genes nevertheless-at least in the lab.
View Article and Find Full Text PDFArcella, a diverse understudied genus of testate amoebae is a member of Tubulinea in Amoebozoa group. Transcriptomes are a powerful tool for characterization of these organisms as they are an efficient way of characterizing the protein-coding potential of the genome. In this work, we employed both single-cell and clonal populations transcriptomics to create a reference transcriptome for Arcella.
View Article and Find Full Text PDFTestate amoebae are eukaryotic microorganisms characterized by the presence of an external shell (test). The shell morphology is used as a diagnostic character, but discordance between morphological and molecular data has been demonstrated in groups of arcellinids (Amoebozoa), one of the principal groups of testate amoebae. Morphology of the test is supposed to differentiate genera and species and it is applied in ecological, monitoring and paleontological studies.
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