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Matsuoka, H.

Publications and source records attributed to Matsuoka, H..

6 recordsLinked to original sources

Genomic properties representing plant sex chromosome evolution interpreted with genome language models

Plants have repeatedly evolved chromosomal sex-determining systems from hermaphroditic ancestors, providing a powerful natural framework for studying convergent evolution. However, sex chromosomes undergo extensive structural divergence, degeneration, and repeat accumulation, making direct comparisons across distant lineages difficult. Here, we apply a genome language model (gLM), which encodes genomic sequences into high-dimensional representations of their contextual properties, to independently evolved sex chromosomes from the distantly related genera Silene and Humulus. Without relying on sequence alignment or gene orthology, we identify convergent genomic signatures shared among plant Y chromosomes, including elevated GC content and depletion of specific trinucleotide motifs. Directionality analyses of latent genomic vectors further reveal common evolutionary trajectories associated with recombination suppression and Y chromosome differentiation. These properties differ from those observed in animal sex chromosomes, suggesting lineage-specific modes of sex chromosome evolution in plants. Our results demonstrate that genome language models can transform structurally incomparable chromosomes into quantitatively comparable evolutionary entities, allowing the interpretation of common genomic principles underlying convergent evolution across deeply diverged plant lineages.

evolutionary biology↗

Live sports spectating promotes oxytocin dynamics and heart rate synchrony in casual fans

Oxytocin has been proposed as a pharmacological target for social dysfunction. However, clinical trials of exogenous oxytocin have yielded modest and inconsistent benefits, highlighting the need for naturalistic, non-pharmacological approaches that recruit endogenous oxytocin. This prospective observational field study examined whether live sports spectating in a modest collegiate setting engages endogenous oxytocin and heart rate synchrony, and how these processes relate to social bonding. Sixty casual spectators at two university basketball games provided salivary samples for oxytocin and cortisol and completed psychological questionnaires before the game, at halftime, and after the game, while heart rate was continuously recorded. Oxytocin dynamics were baseline dependent: individuals with low pre-game oxytocin showed clear increases during spectating, whereas those with high pre-game oxytocin maintained elevated concentrations; across both groups, cortisol decreased and the oxytocin-to-cortisol ratio increased, indicating a shift toward an oxytocin-dominant, low-stress hormonal profile. Live spectating also enhanced heart rate synchrony between spectators, and higher oxytocin levels and stronger synchrony were associated with greater enjoyment, stronger unity with players and fellow fans, higher flow, and stronger intention to revisit. Mediation analyses indicated that perceived unity mediated links between physiological responses and experiential outcomes. These findings identify coordinated oxytocin dynamics and physiological synchrony as candidate mechanisms through which live sports spectating can foster social connection and positive psychological states in everyday, low-stakes settings. Live sports events may represent a simple, scalable non-pharmacological approach to engaging oxytocin-related systems and interpersonal synchrony to promote social connection in everyday life.

neuroscience↗

The evolution of fitness during range expansions in multiple dimensions

We develop a set of programs - the range expansions simulation kit (RESK) - to efficiently simulate range expansions of populations on a square lattice in 1D, 2D (on a strip, and on a disk) and 3D (in a cylinder, and in a sphere). In this study, we present the simulation kit to the public and present some results of using it to simulate a population of diploid individuals with finite genome regions, each containing infinite sites. Specifically, using the programs, we calculate and analyse the temporal evolution of population fitness, as well as fitness on the expansion front, in 3D for the first time. We explore the model over different conditions, compare normalisation methods for fitness, and explore the case of radial (sphere) and axial (cylinder) expansions in 3D, which might apply in the analysis of the different real-life populations, such as viruses/bacteria inside a host, marine species in ocean environments, and potentially in future space colonization planning. In 3D expansions, we find complex spatial fluctuations in deme-average fitness values, different from those in radial 2D expansions. In axial 3D (cylinder) expansions, we determine that the highest-valued deme-average fitness lies along the axis of the expansion. We also find the fluctuation patterns of fitness in 3D cylinder expansions, similar to those previously seen in radial expansions in 2D. In radial 2D (disk) expansions, we find that the fitness of a population undergoing multiple mutations shows a smooth combination of binary segregation pictures against each of those mutations. We confirm the accumulation of deleterious mutations -- a phenomenon known as expansion load -- in all scenarios above. We present the software used in the above to the public as a Julia repository, ready to use with different functions for simulating range expansions with minimal syntax.

genetics↗

Wing musculature reconstruction in extinct flightless auks (Pinguinus and Mancalla) reveals incomplete convergence with penguins (Spheniscidae) due to differing ancestral states

Despite longstanding interest in convergent evolution, factors that result in deviations from fully convergent phenotypes remain poorly understood. In birds, the evolution of flightless wing-propelled diving has emerged as a classic example of convergence, having arisen in disparate lineages including penguins (Sphenisciformes) and auks (Pan-Alcidae, Charadriiformes). Nevertheless, little is known about the functional anatomy of the wings of flightless auks because all such taxa are extinct, and their morphology is almost exclusively represented by skeletal remains. Here, in order to re-evaluate the extent of evolutionary convergence among flightless wing-propelled divers, wing muscles and ligaments were reconstructed in two extinct flightless auks, representing independent transitions to flightlessness: Pinguinus impennis (a crown-group alcid), and Mancalla (a stem-group alcid). Extensive anatomical data were gathered from dissections of 12 species of extant charadriiforms and 4 aequornithine waterbirds including a penguin. It was found that the wings of both flightless auk taxa were characterized by an increased mechanical advantage of wing elevator/retractor muscles, and decreased mobility of distal wing joints, both of which are likely advantageous for wing-propelled diving and parallel similar functional specializations in penguins. However, the conformations of individual muscles and ligaments underlying these specializations differ markedly between penguins and flightless auks, instead resembling those in each respective groups close relatives. Thus, the wings of these flightless wing-propelled divers can be described as convergent as overall functional units, but are incompletely convergent at lower levels of anatomical organization--a result of retaining differing conditions from each groups respective volant ancestors. Detailed investigations such as this one may indicate that, even in the face of similar functional demands, courses of phenotypic evolution are dictated to an important degree by ancestral starting points.

evolutionary biology↗

CTDSP1 inhibitor rabeprazole regulates DNA-PKcs dependent topoisomerase I degradation and irinotecan drug resistance in colorectal cancer

Irinotecan specifically targets topoisomerase I (topoI), and is used to treat various solid tumors, but only 13-32% of patients respond to the therapy. Now, it is understood that the rapid rate of topoI degradation in response to irinotecan causes irinotecan resistance. We have published that the deregulated DNA-PKcs kinase cascade ensures rapid degradation of topoI and is at the core of the drug resistance mechanism of topoI inhibitors, including irinotecan. We also identified CTD small phosphatase 1 (CTDSP1) (a nuclear phosphatase) as a primary upstream regulator of DNA-PKcs in response to topoI inhibitors. Previous reports showed that rabeprazole, a proton pump inhibitor (PPI) inhibits CTDSP1 activity. The purpose of this study was to confirm the effects of rabeprazole on CTDSP1 activity and its impact on colon cancer. Using HCT116 and HT29, with high and low CTDSP1 expression respectively and a retrospective analysis of patients receiving irinotecan with or without rabeprazole have indicated the effect of CTDSP1 in irinotecan response. These results indicate that CTDSP1 promotes sensitivity to irinotecan and rabeprazole prevents this effect, resulting in drug resistance. To ensure the best chance at effective treatment, rabeprazole may not be a suitable PPI for cancer patients treated with irinotecan.

cancer biology↗

Baculovirus-inducing fast-acting innate immunity kills Plasmodium liver stages

Baculovirus (BV), an enveloped insect virus with a circular double-stranded DNA genome, possesses unique characteristics that induce strong innate immune responses in mammalian cells. Here, we show that BV administration not only sterilely protects BALB/c mice for at least 7 days from subsequent Plasmodium berghei sporozoite infection but also eliminates existing liver-stage parasites completely, effects superior to those of primaquine, and does so in a TLR9-independent manner. Six hours post-BV administration, IFN- and IFN-{gamma} were robustly produced in serum, and RNA transcripts of interferon-stimulated genes were drastically upregulated in the liver. The in vivo passive transfer of post-BV administration serum effectively eliminated liver-stage parasites, and IFN- neutralization abolished this effect, indicating that the BV liver-stage parasite killing mechanism is downstream of the type I IFN signaling pathway. Our results demonstrate that BV is a potent IFN-inducing prophylactic and therapeutic agent with great potential for further development as a new malaria vaccine and/or anti-hypnozoite drug.

immunology↗