Biology subjects

Seto, M.

Publications and source records attributed to Seto, M..

3 recordsLinked to original sources

bioRxiv2025

Sex-specific Associations of Gene Expression with Alzheimer's Disease Neuropathology and Ante-mortem Cognitive Performance

The biological mechanisms underlying womens increased Alzheimers disease (AD) prevalence remain undefined. Previous case/control studies have identified sex-biased molecular pathways, but sex-specific relationships between gene expression and AD endophenotypes, particularly sex chromosomes, are underexplored. With bulk transcriptomic data across 3 brain regions from 767 decedents, we investigated sex-specific associations between gene expression and post-mortem {beta}-amyloid and tau as well as antemortem longitudinal cognition. Of 23,118 significant gene associations, 10% were significant in one sex and not the other (sex-specific). Most sex-specific gene associations were identified in females (73%) and associated with tau tangles and longitudinal cognition (90%). Four X-linked genes, MCF2, HDAC8, FTX, and SLC10A3, demonstrated significant sex differences in their associations with AD endophenotypes (i.e., significant sex x gene interaction). Our results also uncovered sex-specific biological pathways, including a female-specific role of neuroinflammation and neuronal development, reinforcing the potential for sex-aware analyses to enhance precision medicine approaches in AD.

neuroscience↗

bioRxiv2024

Thermodynamics Underpinning the Microbial Community-Level Nitrogen Networks

Nitrogen species often serve as crucial electron donors or acceptors in microbial catabolism, enabling the synthesis of adenosine triphosphate (ATP). Although theoretically any nitrogen redox reactions could be an energy source, it remains unclear why specific reactions are predominantly utilized. This study evaluates energetically superior reactions from 988 theoretically plausible combinations involving 11 nitrogen species, oxygen gas, hydrogen ion, and water. Our analysis of the similarity between this model-based energetically superior network and the actual microbial community-level nitrogen network, reconstructed as a combination of enzymatic reactions, showed increased link overlap rates with thermodynamic weighting on reaction rates. In particular, existing microbial reactions involving solely nitrogen species and additionally oxygen, such as anaerobic ammonia oxidation (ANAMMOX) and complete and partial nitrification, were frequently identified as energetically superior among the examined reactions. The alignment of these reactions with thermodynamically favorable outcomes underscores the critical role of thermodynamics not only in individual metabolic processes but also in shaping the broader network interactions within ecosystems, consequently affecting biodiversity and ecological functions. Significance StatementThis study advances our understanding of how thermodynamics governs energy metabolism at the community level within microbial ecosystems by systematically analyzing 988 potential redox reactions involving inorganic nitrogen species, oxygen gas, hydrogen ion, and water. We uncover that existing microbial reactions, such as anaerobic ammonia oxidation (ANAMMOX) and nitrification, stand out as energetically superior over other examined reactions. The robust alignment between model-predicted energetically favorable reactions and actual microbial nitrogen reactions underscores the predictive power of thermodynamic principles, even in ecological networks. Our findings extend the traditional applications of thermodynamics in biology, highlighting how thermodynamic constraints shape ecological networks and influence biodiversity and ecosystem functions in natural ecosystems.

ecology↗

bioRxiv2023

Survivability and Life Support in Sealed Mini-Ecosystems with Simulated Planetary Soils

Establishing a sustainable life-support system for space exploration is challenging due to the vast distances, costs, and differing environments from Earth. Using insights from the Biosphere 2 experiment, we introduced the "Ecosphere" and "Biosealed" systems in custom containers to replicate Earths ecosystems, suggesting feasible space migration through transplanting Earth-like biomes. Over four years, we gained deeper insights into these enclosed ecosystems. Moisture deficiency was a major obstacle to plant growth, which we addressed by incorporating a groundwater layer in the containers. We underscored the critical role of microorganisms in building and sustaining these ecosystems. However, temperature spikes from sunlight threatened stability. Our experiments confirmed fruit flies survival on plant-produced oxygen and photosynthetic bacteria. Interactions between plants, microbes, and simulated space soils were examined. Detailed analysis unveiled diverse microbes shaping both confined and simulated space environments. Major findings include the symbiotic relationship of plants with cyanobacteria, the potential of LED lighting in sun-limited missions, and challenges with ethylene gas and moisture. Microbial integration in rough soils holds promise for seed germination, but understanding their role in space soils is crucial. Our research offers a comprehensive foundation for future space life-support systems and underlines potential concerns about microbes affecting human health.

ecology↗