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Biology subjects

Koike, H.

Publications and source records attributed to Koike, H..

8 recordsLinked to original sources

An immune receptor pair consisting of NLR and MLKL confers stable resistance against Pyricularia oryzae pathotype Eluesine on wheat by recognition of three effectors

Kinase fusion proteins (KFPs) have emerged as an important group of immune receptors encoded by plant resistance genes. Here, we report a new type of gene pair that controls resistance of wheat to the blast fungus, Pyricularia oryzae. We cloned a fungal gene involved in avirulence of P. oryzae pathotype Eleusine on wheat and designated it PWT8. We also identified its corresponding resistance gene in wheat, and tentatively named it Rwt8. This resistance gene was located at the same locus as previously identified resistance genes Rwt3 and Rwt6. Molecular cloning revealed that Rwt3, Rwt6, and Rwt8 were the same gene consisting of an identical gene pair, one encoding an NLR and the other encoding a mixed lineage kinase-like (MLKL) protein. These two genes were closely linked in a head-to-head orientation and behaved as a single gene. This gene pair recognized three AVR genes, PWT3, PWT6, and PWT8, and was designated Rwt3.6.8. The distribution of Rwt3.6.8 in common wheat landraces suggested that the gene pair may have been a factor which the D genome provided to the genus Triticum to broaden its adaptability to various environments in the world, especially in Asia and Africa.

plant biology↗

Gaze information enhances remote skill transfer of piano performance

Remote instruction is increasingly used to teach complex sensorimotor skills, yet conventional audio-video communication poorly conveys the fine-grained attentional cues that support expert guidance. This study tested whether real-time bidirectional gaze sharing enhances remote transfer of piano performance skill by restoring joint visual attention between teacher and learner. Twenty-seven conservatory-level pianists were randomly assigned either to a group, in which teacher and learner gaze positions were visualized during online instruction, or to a group receiving otherwise identical instruction without gaze cues. We recorded eye movements with wearable eye trackers and evaluated piano performance using a high-resolution key-motion sensing system. Real-time gaze sharing increased learners gaze-pattern similarity to a teacher, which was not evident in the control group. A parallel effect was observed for head-movement similarity. Critically, gaze sharing also reduced variability of the key-descending velocity at the moment of finger-key contact for the right-hand landing after a leap, a feature associated with unstable key-striking velocity. These findings exhibit that gaze information is not merely an auxiliary communication cue but a timing-critical coordination channel for remote motor instruction. By augmenting video-mediated pedagogy with shared attentional dynamics, the proposed system offers a framework for transmitting tacit, high-dexterity skills across distance.

neuroscience↗

Primitive Hepatoblasts Driving Early Liver Development

The embryonic development of the liver is initiated by the emergence of hepatoblasts, originating from the ventral foregut endoderm adjacent to the heart. Here, we identify and characterize a previously unrecognized population of early hepatoblasts at the ventroposterior part of the emerging liver bud, traced from Cdx2-positive endoderm progenitors, which we term primitive hepatoblasts. Mouse and human single-cell transcriptomics reveals the expression of both canonical hepatoblast markers TBX3, FGB, and KRT8/18 and primitive-specific mesenchymal markers ID3, VIM, and GATA4. Lineage tracing revealed the notable contribution up to 12.6% of LIV2+ hepatoblasts at E11.5 but diminishes in late fetal and postnatal development. Epigenetic and functional perturbation studies further uncover that primitive hepatoblast emergence is primed by WNT-suppression on RA-permissive CDX2+FOXA2+ progenitors. Furthermore, human pluripotent stem cell-derived primitive hepatoblast-like cells secrete pleiotrophin and midkine to amplify hepatoblast populations and develop epithelial-mesenchymal hybrid tissues in vivo. Our results provide a new framework for understanding lineage heterogeneity during early hepatogenesis and offer revised insights into strategies to model normal and abnormal liver development.

developmental biology↗

Task Demand-dependent Contribution of Frontal-Sensory Cortical Projections to Attentional Behavior in Mice

Top-down attention is a dynamic cognitive process that facilitates the detection of the task-relevant stimuli from our complex sensory environment. A neural mechanism capable of deployment under specific task-demand conditions would be crucial to efficiently control attentional processes and improve promote goal-directed attention performance during fluctuating attentional demand. Previous studies have shown that frontal top-down neurons projecting from the anterior cingulate area (ACA) to the visual cortex (VIS; ACAVIS) are required for visual attentional behavior during the 5-choice serial reaction time task (5CSRTT) in mice. However, it is unknown whether the contribution of these projecting neurons is dependent on the extent of task demand. Here, we first examined how behavior outcomes depend on the number of locations for mice to pay attention and touch for successful performance, and found that the 2-choice serial reaction time task (2CSRTT) is less task demanding than the 5CSRTT. We then employed optogenetics to demonstrate that suppression ACAVIS projections immediately before stimulus presentation has no effect during the 2CSRTT in contrast to the impaired performance during the 5CSRTT. These results suggest that ACAVIS projections are necessary when task demand is high, but once a task demand is lowered, ACAVIS neuron activity becomes dispensable to adjust attentional performance. These findings support a model that the frontal-sensory ACAVIS projection regulates visual attention behavior during specific high task demand conditions, pointing to a flexible circuit-based mechanism for promoting attentional behavior.

neuroscience↗

NANOS2 suppresses the cell cycle by repressing mTORC1 activators in embryonic male germ cells

During murine germ cell development, male germ cells enter the mitotically arrested G0 stage, which is an initial step of sexually dimorphic differentiation. The male specific RNA-binding protein NANOS2 has a key role in suppressing the cell cycle in germ cells. However, the detailed mechanism of how NANOS2 regulates the cell cycle remains unclear. Using single-cell RNA sequencing (scRNA-seq), we extracted the cell cycle state of each germ cell in wild-type and Nanos2-KO testes, and revealed that Nanos2 expression starts in mitotic cells and induces mitotic arrest. We also found that NANOS2 and p38 MAPK work in parallel to regulate the cell cycle, suggesting that several different cascades are involved in the induction of cell cycle arrest. Furthermore, we identified Rheb, a regulator of mTORC1, and Ptma as possible targets of NANOS2. We propose that the repression of the cell cycle is a primary function of NANOS2 and that it is mediated via the suppression of mTORC1 activity by repressing Rheb in a post-transcriptional manner.

developmental biology↗

An adolescent sensitive period of heightened frontal top-down projection activity promotes local circuit integration and attentional behavior

Frontal top-down cortical neurons projecting to sensory cortical regions are well-positioned to integrate long-range inputs with local circuitry in frontal cortex to implement top-down attentional control of sensory regions. How adolescence contributes to the maturation of top-down neurons and associated local/long-range input balance, and the establishment of attentional control is poorly understood. Here we combine projection-specific electrophysiological and rabies-mediated input mapping in mice to uncover adolescence as a developmental stage when frontal top-down neurons projecting from the anterior cingulate to visual cortex are highly functionally integrated into local excitatory circuitry and have heightened activity compared to adulthood. Chemogenetic suppression of top-down neuron activity selectively during adolescence, but not later periods, produces long-lasting visual attentional behavior deficits, and results in excessive loss of local excitatory inputs in adulthood. Our study reveals an adolescent sensitive period when top-down neurons integrate local circuits with long-range connectivity to produce attentional behavior.

neuroscience↗

Single cell transcriptomics reveals a signaling roadmap coordinating endoderm and mesoderm lineage diversification during foregut organogenesis

Visceral organs, such as the lungs, stomach, liver and pancreas, are derived from the fetal foregut through a series of inductive interactions between the definitive endoderm (DE) and the surrounding splanchnic mesoderm (SM). While patterning of DE lineages has been fairly well studied, paracrine signaling controlling SM regionalization and how this is coordinated with the epithelial identity during organogenesis is obscure. Here we used single cell transcriptomics to generate a high-resolution cell state map of the embryonic mouse foregut. This uncovered an unexpected diversity in the SM cells that developed in close register with the organ-specific epithelium. From these data, we inferred a spatiotemporal signaling roadmap of the combinatorial endoderm-mesoderm interactions that orchestrate foregut organogenesis. We validated key predictions with mouse genetics, showing the importance of endoderm-derived signals in mesoderm patterning. Finally, leveraging the signaling road map we generated different SM subtypes from human pluripotent stem cells (hPSCs), which previously have been elusive. The single cell data can be explored at: https://research.cchmc.org/ZornLab-singlecell.

developmental biology↗

Long-read sequencing identifies GGC repeat expansion in human-specific NOTCH2NLC associated with neuronal intranuclear inclusion disease

Neuronal intranuclear inclusion disease (NIID) is a progressive neurodegenerative disease characterized by eosinophilic hyaline intranuclear inclusions in neuronal and somatic cells. The wide range of clinical manifestations in NIID makes ante-mortem diagnosis difficult 1-8, but skin biopsy realized its ante-mortem diagnosis 9,10 and many NIID cases have been diagnosed by skin biopsy11,12. Most cases of NIID are sporadic, but several familial cases are known. Using a large NIID family, we conducted linkage mapping, found a 58.1-Mb linked-region at 1p22.1-q21.3 with a maximum logarithm of odds (LOD) score of 4.21, and successfully identified a GGC repeat expansion in the 5 portion of NOTCH2NLC in all affected members by long-read sequencing, but not in unaffected members. We further found the similar expansions in additional 8 unrelated families with NIID as well as 39 sporadic NIID patients. Repeat-primed PCR consistently detected the GGC repeat expansion in all the familial and sporadic patients diagnosed by skin biopsy, but never in unaffected family members nor 200 controls. This shows that pathogenic changes in a human-specific gene evolutionarily generated by segmental duplication indeed causes a human disease.

genetics↗