Biology subjects

Murata, A.

Publications and source records attributed to Murata, A..

5 recordsLinked to original sources

bioRxiv2026

Global distributions and plant associations of the ecologically diverse ascomycete order Helotiales

Background Fungi in plant root systems are key to understanding the dynamics and functioning of terrestrial ecosystems. Whereas our knowledge of below-ground plant-fungus symbioses has derived mainly from studies of mycorrhizal and pathogenic fungi, recent studies have uncovered an unexpected diversity of ecological niches occupied by root-associated fungi. The fungal order Helotiales is conspicuous in this respect because this predominantly root-associated taxon encompasses a broad ecological spectrum, ranging from saprotrophic and pathogenic fungi to endophytic and mycorrhizal fungi with plant growth-promoting functions. In this study, we integrated a worldwide dataset of 1,996 Helotiales Species Hypotheses (i.e., species-level taxa tentatively defined based on DNA sequences) detected in roots of 362 plant genera representing 117 families and 47 orders, and systematically quantified the specificity of Helotiales-plant associations. Results The analysis of 37,688 unique occurrence records of Helotiales fungi across 1,940 global sampling locations revealed highly structured associations between Helotiales genera and plant lineages, exemplified by the strong specificity of Hyaloscypha, Oidiodendron, and Phialocephala for Pinales and that of Glutinomyces for Fagales, even after statistically controlling background biogeographic patterns. At the Species-Hypothesis-level analysis, major clades within the Helotiales phylogeny consistently exhibited high specificity for Pinaceae, whereas highly specific associations with other ectomycorrhizal, arbuscular mycorrhizal, and nonmycorrhizal plants were restricted to small terminal clades of the fungal phylogeny. Conclusions The integration of ecological specificity and phylogenetic analyses suggests the possibility that Helotiales fungi established close associations with Pinaceae early in their evolutionary history and subsequently underwent host shifts to diverse angiosperm lineages. Given the emerging evidence that Helotiales fungi play pivotal ecological and physiological roles in plant root systems, these statistical insights into Helotiales-plant associations provide a fundamental basis for understanding the evolutionary history and functioning of terrestrial ecosystems.

microbiology↗

bioRxiv2026

Environmental filtering and host identity collectively shape root-associated microbiomes of Ericaceae and ectomycorrhizal plants in fumarole fields

Background Symbiosis with microbes is a key strategy that has enabled plants to colonize extreme environments. Since the benefits conferred by root-associated microbes depend on both environmental conditions and host-microbe combinations, plant adaptation to harsh environments is closely linked to the assembly of root microbial communities. Understanding how environmental and host filtering jointly shape these communities is therefore fundamental to elucidating the mechanisms underlying plant adaptation to extreme environments. Results In this study, we investigated the differentiation of root-associated prokaryotic and fungal communities and individual operational taxonomic units (OTUs) across two contrasting habitats surrounding fumaroles, solfatara-field and forest-edge habitats, and six dominant Ericaceae and ectomycorrhizal plant taxa. Prokaryotic and fungal OTUs rarely exhibited strong preferences for both habitat and host identity. Instead, many of prokaryotic and fungal OTUs specialized to one of these niches, collectively generating root microbial communities differentiated by both factors. Nonetheless, striking specializations in habitat and host niches were observed in the fungal family Hyaloscyphaceae (Helotiales). To gain insight into the evolutionary basis of microbial specialization, we examined phylogenetic signals in preference phenotypes. The resulting weak phylogenetic signals in these preference phenotypes further suggest that this fungal clade has undergone substantial ecological divergence. Conclusion Overall, our findings indicate that root-associated microbial communities in extreme environments are assembled through the accumulation of microbial taxa specialized to either habitat or host, and that strong ecological specialization in fungi can arise with little phylogenetic constraint.

microbiology↗

bioRxiv2026

EMPAC: A Multimodal Dataset for Bridging Affective and Cognitive Empathy

Empathy, a key element of social interaction, involves both cognitive and affective processes and is commonly investigated through measures such as empathic accuracy and affective physiological synchrony. While physiological synchrony offers a continuous measure of affective processes, empathic accuracy typically relies on discrete self-reports, leaving their temporal relationship largely unexplored. Advancing this line of research requires datasets that integrate time-continuous self-reports with physiological signals, yet such datasets--particularly those focusing on the empathizee--remain limited. To fill this gap, we present EMPAC (Empathy Measurement: Physiological, Affective, and Cognitive), a multimodal dataset constructed. To create empathy-eliciting stimuli, professional actors performed emotionally intense, pseudo-autobiographical narratives while their physiological signals (e.g., ECG, EDA) and continuous self-reported emotional states were recorded. We then conducted two observer experiments using these video recordings. In Experiment 1, to validate the stimuli as empathy-eliciting materials, observers continuously rated emotional intensity without being informed of the specific emotion portrayed, following the protocol of previous studies on time-series empathic accuracy. Yet this approach sometimes revealed a gap between the emotion category portrayed by the target and that perceived by the observers. In Experiment 2, we introduced a revised procedure in which the target emotion category was disclosed prior to viewing, revealing that specifying the target emotion led to a different relationship between individual empathy traits and empathic accuracy than observed in Experiment 1. EMPAC thus provides a rich, temporally aligned resource for investigating empathy dynamics in naturalistic settings and for evaluating methodological variations in empathic accuracy paradigms.

neuroscience↗

bioRxiv2025

Opponent-flipping tactics in aggressive interactions of the cricket Gryllus bimaculatus

Male crickets engage in intense aggressive behavior, competing for resources. In this study, we focus on the quick movements during tactile combat in the cricket fight, to understand how they defeat the opponents. We performed kinematic analysis following high-speed cam recording of the fight. High-speed cam recordings showed that the attacker jumped to the head of the attacked cricket and thrusted it backwards. The attacked cricket was sometimes flipped over and tended to retreat. To understand how the attacker jumps effectively to flip over the opponent, we compared the attack-jump and escape-jump. The kinematics analysis demonstrated that the attack motion is different from the jump in the case of escaping from threats. The attacker cricket adjusted the direction of its body using its forelegs. The mandibles were used to hook onto the head of the attacked cricket. The attacked cricket moved its hindlegs with different kinematics to jump in the case of escape and exerted greater velocity. These findings advance our knowledge of how animals utilize their body depending on the situation.

animal behavior and cognition↗

bioRxiv2022

FUS regulates RAN translation through modulating the G-quadruplex structure of GGGGCC repeat RNA in C9orf72-linked ALS/FTD

Abnormal expansions of GGGGCC repeat sequence in the noncoding region of the C9orf72 gene is the most common cause of familial amyotrophic lateral sclerosis and frontotemporal dementia (C9-ALS/FTD). The expanded repeat sequence is translated into dipeptide repeat proteins (DPRs) by noncanonical repeat-associated non-AUG (RAN) translation. Since DPRs play central roles in the pathogenesis of C9-ALS/FTD, we here investigate the regulatory mechanisms of RAN translation, focusing on the effects of RNA-binding proteins (RBPs) targeting GGGGCC repeat RNAs. Using C9-ALS/FTD model flies, we demonstrated that the ALS/FTD-linked RBP FUS suppresses RAN translation and neurodegeneration in an RNA-binding activity-dependent manner. Moreover, we found that FUS directly binds to and modulates the G-quadruplex structure of GGGGCC repeat RNA as an RNA chaperone, resulting in the suppression of RAN translation in vitro. These results reveal a previously unrecognized regulatory mechanism of RAN translation by G-quadruplex-targeting RBPs, providing therapeutic insights for C9-ALS/FTD and other repeat expansion diseases.

neuroscience↗