On the origin of the nucleus: a hypothesis

Microbiology and Molecular Biology Reviews, Journal Year: 2023, Volume and Issue: 87(4)

Published: Nov. 29, 2023

SUMMARY In this hypothesis article, we explore the origin of eukaryotic nucleus. doing so, first look afresh at nature defining feature cell and its core functions—emphasizing utility seeing nucleoplasm cytoplasm as distinct regions a common compartment. We then discuss recent progress in understanding evolution from archaeal bacterial ancestors, focusing on phylogenetic experimental data which have revealed that many machines with nuclear activities counterparts. addition, review literature describing biology representatives TACK Asgardarchaeaota - closest known living relatives eukaryotes. Finally, bringing these strands together, propose model for nucleus explains much current data, including predictions can be used to put test.

Language: Английский

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An evolutionary timescale for Bacteria calibrated using the Great Oxidation Event

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: Aug. 11, 2023

Most of life’s diversity and history is microbial but it has left a meagre fossil record, greatly hindering understanding evolution in deep time. However, the co-evolution life Earth system signatures bacterial metabolism geochemical most conspicuously Great Oxidation Event (GOE) ∼2.33 billion years ago (Ga, (Poulton et al. 2021)), which oxygenic photosynthesis tectonism (Eguchi, Seales, Dasgupta 2019) transformed Earth’s biosphere from dominantly anaerobic to aerobic. Here, we combine machine learning phylogenetic reconciliation infer ancestral transitions aerobic lifestyles during evolution. Linking these GOE provides new constraints timetree Bacteria. We find that extant phyla are truly ancient, having radiated Archaean Proterozoic: oldest include Bacillota (Firmicutes), 3.1-3.7 Ga, Cyanobacteria (3.3-3.5 Ga) Patescibacteria (3-3.5 Ga). show were ancestrally an lifestyle post-dated GOE. Our analyses trace oxygen production consumption back Cyanobacteria. From starting point, horizontal transfer seeded across over hundreds millions years. demonstrate diversification aerobes proceeded two waves corresponding second sustained rise atmospheric O 2 at dawn Palezoic (Krause 2022).

Language: Английский

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Several independent adaptations of archaea to hypersaline environments

bioRxiv (Cold Spring Harbor Laboratory), Journal Year: 2023, Volume and Issue: unknown

Published: July 3, 2023

Abstract Several archaeal lineages thrive in high, saturating salt concentrations. These extremely halophilic archaea, including Halobacteria, Nanohaloarchaeota, Methanonatronarchaeia, and Haloplasmatales, must maintain osmotic equilibrium with their environment. For this, they use a ‘salt-in’ strategy, which involves pumping molar concentrations of potassium into the cells, which, turn, has led to extensive proteome-wide modifications prevent protein aggregation. However, evolutionary history underlying these adaptations remains poorly understood. In particular, number times that dramatic proteome-sweeping changes occurred is unclear due conflicting phylogenetic positions found for several lineages. Here, we present resolved phylogeny archaea obtained using improved taxon sampling state-of-the-art approaches designed cope strong compositional biases proteomes. We describe two new uncultured lineages, Afararchaeaceae Asboarchaeaceae, break long branches at base Haloarchaea respectively. Our phylogenomic analyses show least four independent extreme halophily during evolution. Finally, gene-tree/species-tree reconciliation suggests gene duplication horizontal transfer played an important role this process, example, by spreading key genes (such as those encoding transporters) across various

Language: Английский

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Studying the Human Microbiota: Advances in Understanding the Fundamentals, Origin, and Evolution of Biological Timekeeping

International Journal of Molecular Sciences, Journal Year: 2023, Volume and Issue: 24(22), P. 16169 - 16169

Published: Nov. 10, 2023

The recently observed circadian oscillations of the intestinal microbiota underscore profound nature human-microbiome relationship and its importance for health. Together with discovery clocks in non-photosynthetic gut bacteria rhythms anucleated cells, these findings have indicated possibility that virtually all microorganisms may possess functional biological clocks. However, they also raised many essential questions concerning fundamentals timekeeping, evolution, origin. This narrative review provides a comprehensive overview recent literature molecular chronobiology, aiming to bring together latest evidence on structure mechanisms driving microbial while pointing potential applications this knowledge medicine. Moreover, it discusses hypotheses regarding evolution timing describes functions peroxiredoxins cells their contribution cellular clockwork. diversity among various human-associated role transcriptional post-translational timekeeping are addressed. Finally, metabolic oscillators host-microbiome communication is presented.

Language: Английский

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