Biology subjects

Diao, M.

Publications and source records attributed to Diao, M..

9 recordsLinked to original sources

bioRxiv2025

Cognitive effects of placebo antipsychotics: Investigating their mechanisms using event-related potentials (ERPs) in a cognitive test and a self-referential task

Placebos modulate neurocognitive processes. We examined whether a fully deceptive antipsychotic-placebo changes cognition not only by enhancing arousal and attention but also by changing self-representations, namely, by adding that of being under a treatment related to psychosis and by weakening the binding of experience to reality. Drug-naive healthy participants (N = 83) were split into a group (N = 40) who took a pill described as an antipsychotic and a no-pill control group (N = 43). Participants performed a cognitive test (CogTest), that is, a semantic categorization task and a self-referential role judgment task (SRT). Behavioral responses and event-related potentials (ERPs) were recorded. In the CogTest, placebos showed faster response times and higher accuracy than no-pills. This cognitive improvement was associated with more negative occipito-temporal early ERPs (OTEEs), larger central P2s (CentP2s), and larger late positive potentials (LPPs), with the latter correlating with response times. As in the literature, CentP2s were maximal in the SRT, possibly because it maximally stimulates the binding of the stimulus to long-term self-representations. The larger CentP2s and LPPs for placebos than for no-pills in the CogTest were thus tentatively related to the binding of the stimulus with egocentric self-representations, temporarily enriched by the addition of the representation of being on drug. On the contrary, the more negative OTEEs were related to a weaker binding to allocentric ones, preventing a strong binding of experience with reality. The smaller N400s observed for placebos than for no-pills in both tasks were related to greater openness to new experiences.

neuroscience↗

bioRxiv2024

Aerobic methane production by methylotrophic Methylotenera in groundwater

Methylotenera are signature denitrifiers and methylotrophs commonly found together with methanotrophic bacteria in lakes and freshwater sediments. Here we show that three distinct Methylotenera ecotypes were abundant in methane-rich, Pleistocene-aged groundwaters. Just like in surface water biomes, groundwater Methylotenera often co-occurred with methane-oxidizing bacteria, even though they were generally unable to denitrify. One abundant Methylotenera ecotype expressed a pathway for aerobic methane production from methylphosphonate. This phosphate-acquisition strategy was recently found to contribute to methane production in the oligotrophic, oxic upper ocean. Gene organization, phylogeny and 3D protein structure of the key enzyme, C-P lyase subunit PhnJ were consistent with a role in phosphate uptake. We conclude that phosphate may be a limiting nutrient in productive, methane rich aquifers and that methylphosphonate degradation can contribute to groundwater methane production.

microbiology↗

bioRxiv2023

High diversity, abundance and expression of hydrogenases in groundwater

Hydrogen may be the most important electron donor available in the subsurface. Here we analyze the diversity, abundance and expression of hydrogenases in 5 proteomes, 25 metagenomes and 265 amplicon datasets of groundwaters with diverse geochemistry. A total of 1,772 new [NiFe]-hydrogenase gene sequences were recovered, which almost doubled the number of sequences in a widely used database. [NiFe]-hydrogenases were highly abundant, almost as abundant as the DNA-directed RNA polymerase. The abundance of hydrogenase genes increased with depth from 0 to 129 m. Hydrogenases were present in 502 out of 1,245 metagenome-assembled-genomes. The populations with hydrogenases accounted for [~]50% of all populations. Hydrogenases were actively expressed, making up as much as 5.9% of methanogen proteomes. Most of the newly discovered diversity of hydrogenases was in "Group 3b", which was linked to sulfur metabolism. "Group 3d" was the most abundant, which was previously linked to fermentation, but we observed this group mainly in methanotrophs and chemoautotrophs. "Group 3a", associated with methanogenesis, was the most active in proteomes. Two newly discovered groups of [NiFe]-hydrogenases further expanded the biodiversity. Our results highlight the vast diversity, abundance and expression of hydrogenases in the sampled groundwaters, suggesting a high potential for hydrogen oxidation in subsurface habitats.

microbiology↗

bioRxiv2023

Global diversity and inferred ecophysiology of microorganisms with the potential for dissimilatory sulfate/sulfite reduction

Sulfate/sulfite-reducing microorganisms (SRM) are ubiquitous in nature, driving the global sulfur cycle. A hallmark of SRM is the dissimilatory sulfite reductase encoded by the paralogous genes dsrAB. Based on analysis of 950 mainly metagenome-derived dsrAB-encoding genomes, we redefine the global diversity of microorganisms with the potential for dissimilatory sulfate/sulfite reduction and uncover genetic repertoires that challenge earlier generalizations regarding their mode of energy metabolism. We show: (i) 19 out of 23 bacterial and 2 out of 4 archaeal phyla harbor uncharacterized SRM, (ii) four phyla including the Desulfobacterota harbor microorganisms with the genetic potential to switch between sulfate/sulfite reduction and sulfur oxidation, and (iii) the combination as well as presence/absence of different dsrAB-types, dsrL-types and dsrD provides guidance on the inferred direction of dissimilatory sulfur metabolism. We further provide an updated dsrAB database including >60% taxonomically resolved, uncultured family-level lineages and recommendations on existing dsrAB primers for environmental surveys. Our work summarizes insights into the inferred ecophysiology of newly discovered SRM, puts SRM diversity into context of the major recent changes in bacterial and archaeal taxonomy, and provides an up-to-date framework to study SRM in a global context. One sentence summarySulfate/sulfite reducing microorganisms are shaping Earths interconnected sulfur and carbon cycles since the Archaean: this legacy unfolds in 27 archaeal and bacterial phyla encountered in diverse marine, terrestrial, and deep-subsurface environments.

microbiology↗

bioRxiv2022

Hydrogen and dark oxygen drive microbial productivity in diverse groundwater ecosystems

Groundwater ecosystems are globally wide-spread yet still poorly understood. We investigated the age, aqueous geochemistry, and microbiology of 138 groundwater samples from 87 monitoring wells (<250m depth) located in 14 aquifers in the Canadian Prairie. Geochemistry and microbial ecology were tightly linked revealing large-scale aerobic and anaerobic hydrogen, methane, nitrogen, and sulfur cycling carried out by diverse microbial communities. Older groundwaters contained on average more cells (up to 1.4x107/mL) than younger ground-waters. Organic carbon-rich strata featured some of the highest abundances, challenging current estimates of global groundwater population sizes. Substantial concentrations of dissolved oxygen (n=57; 0.52{+/-}0.12 mg/L [mean{+/-}SE]; 0.39 mg/L [median]) in older groundwaters could support aerobic lifestyles in subsurface ecosystems at an unprecedented scale. Metagenomics, oxygen isotope analyses and mixing models indicated that microbial "dark oxygen" contributed to the dissolved oxygen pool in subsurface ecosystems commonly assumed to be anoxic.

microbiology↗

bioRxiv2022

Frequency of change determines effectiveness of microbial response strategies in sulfidic stream microbiomes

Nature challenges microbes with change at different frequencies and demands an effective response for survival. Here, we used controlled laboratory experiments to investigate the ecological success of different response strategies, such as post-translational modification, transcriptional regulation, and specialized versus adaptable metabolisms. For this, we inoculated replicated chemostats with an enrichment culture obtained from sulfidic stream microbiomes 16 weeks prior. The chemostats were submitted to alternatingly oxic and anoxic conditions at three frequencies, with periods of 1 day, 4 days and 16 days. The microbial response was recorded with 16S rRNA gene amplicon sequencing, shotgun metagenomics, transcriptomics and proteomics. Metagenomics resolved 26 nearly complete genomes of bacterial populations, mainly affiliated with Proteobacteria and Bacteroidetes. Almost all these populations maintained a steady growth rate under both redox conditions at all three frequencies of change. Apparently, oscillating oxic/anoxic conditions selected for generalistic species, rather than species specializing in only a single condition. Rapid (1-day) dynamics yielded more stochasticity, both in community dynamics and gene expression, indicating that bet-hedging might be an effective coping strategy for relatively rapid environmental change. Codon-usage bias, previously associated with copiotrophic and oligotrophic lifestyles, was found to be a powerful predictor of ecological success at different frequencies, with copiotrophs and oligotrophs more successful at a rapid and a slow pace of change, respectively, independent of growth rate.

microbiology↗

bioRxiv2020

PSGL-1 inhibits HIV-1 infection by restricting actin dynamics and sequestering HIV envelope proteins

PSGL-1 has recently been identified as an HIV restriction factor that inhibits HIV DNA synthesis and more potently, virion infectivity. But the underlying mechanisms of these inhibitions are unknown. Here we show that PSGL-1 directly binds to cellular actin filaments (F-actin) and restricts actin dynamics, which leads to inhibition of HIV DNA synthesis. PSGL-1 is incorporated into nascent virions and restricts actin dynamics in the virions, which partially accounts for the inhibition of virion infectivity. More potently, PSGL-1 inhibits incorporation of Env proteins into nascent virions, leading to loss of envelope spikes on the virions as shown by Cryo-electron microscopy and super-resolution imaging. This loss is associated with a profound defect in viral entry. Mechanistically, PSGL-1 binds gp41 and sequesters gp41 at the plasma membrane, explaining the inhibition of Env incorporation in nascent virions. PSGL-1s dual anti-HIV mechanisms represent novel strategies of human cells to defend against HIV infection.

microbiology↗

bioRxiv2020

Organized cannabinoid receptor distribution in neurons revealed by super-resolution fluorescence imaging

G-protein-coupled receptors (GPCRs) play important roles in cellular functions. However, their intracellular organization is largely unknown. Through investigation of the cannabinoid receptor 1 (CB1), we discovered periodically repeating clusters of CB1 hotspots within the axons of neurons. We observed these CB1 hotspots interact with the membrane-associated periodic skeleton (MPS) forming a complex crucial in the regulation of CB1 signaling. Furthermore, we found that CB1 hotspot periodicity increased upon CB1 agonist application, and these activated CB1 displayed less dynamic movement compared to non-activated CB1. Our results suggest that CB1 forms periodic hotspots organized by the MPS as a mechanism to increase signaling efficacy when being activated.

neuroscience↗

bioRxiv2019

A SAC phosphoinositide phosphatase controls rice development via hydrolyzing phosphatidylinositol 4-phosphate and phosphatidylinositol 4,5-bisphosphate

Phosphoinositides (PIs) as regulatory membrane lipids play essential roles in multiple cellular processes. Although the exact molecular targets of PIs-dependent modulation remain largely elusive, the effects of disturbed PIs metabolism could be employed to propose regulatory modules associated with particular downstream targets of PIs. Here, we identified the role of GRAIN NUMBER AND PLANT HEIGHT 1 (GH1), which encodes a suppressor of actin (SAC) domain-containing phosphatase with unknown function in rice. Endoplasmic reticulum-localized GH1 specifically dephosphorylated and hydrolyzed phosphatidylinositol 4-phosphate (PI4P) and phosphatidylinositol 4,5-bisphosphate [PI(4,5)P2]. Inactivation of GH1 resulted in massive accumulation of both PI4P and PI(4,5)P2, while excessive GH1 caused their depletion. Notably, superabundant PI4P and PI(4,5)P2 could both disrupt actin cytoskeleton organization and suppress cell elongation. Interestingly, both PI4P and PI(4,5)P2 inhibited actin-related proteins 2 and 3 (Arp2/3) complex-nucleated actin branching networks in vitro, whereas PI(4,5)P2 showed more dramatic effect in a dose-dependent manner. Overall, the overaccumulation of PI(4,5)P2 resulted from dysfunction of SAC phosphatase possibly perturbs Arp2/3 complex-mediated actin polymerization, thereby disordering the cell development. These findings imply that Arp2/3 complex might be the potential molecular target of PI(4,5)P2-dependent modulation in eukaryotes, thereby providing new insights into the relationship between PIs homeostasis and plants growth and development.

plant biology↗