Publications by authors named "Shota Morikawa"

The regulation of virulence in plant-pathogenic fungi has emerged as a key area of importance underlying host infections. Recent work has highlighted individual transcription factors (TFs) that serve important roles. A prominent example is PnPf2, a member of the Zn2Cys6 family of fungal TFs, which controls the expression of effectors and other virulence-associated genes in Parastagonospora nodorum during infection of wheat.

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The fungus Parastagonospora nodorum causes septoria nodorum blotch on wheat. The role of the fungal Velvet-family transcription factor VeA in P. nodorum development and virulence was investigated here.

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Heart rate (HR) can be voluntarily regulated when individuals receive real-time feedback. In a rat model of HR biofeedback, the neocortex and medial forebrain bundle were stimulated as feedback and reward, respectively. The rats reduced their HR within 30 minutes, achieving a reduction of approximately 50% after 5 days of 3-hour feedback.

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As animals explore environments, hippocampal place cells sequentially fire at progressively earlier phases of theta oscillations in hippocampal local field potentials. In this study, we evaluated the network-level significance of theta phase-entrained neuronal activity in organizing place cell spike patterns. A closed-loop system was developed in which optogenetic stimulation with a temporal pattern replicating theta phase precession is delivered to hippocampal CA1 neurons when rats traversed a particular region on a linear track.

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In some models, animals approach aversive stimuli more than those housed in an enriched environment. Here, we found that male mice in an impoverished and unstimulating (i.e.

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The ventral hippocampus (vHC) is a core brain region for emotional memory. Here, we examined how the vHC regulates stress susceptibility from the level of gene expression to neuronal population dynamics in male mice. Transcriptome analysis of samples from stress-naïve mice revealed that intrinsic calbindin (Calb1) expression in the vHC is associated with susceptibility to social defeat stress.

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In this study, we described the isolation of an 8,14-secoergostane-type, a 9,11-secoergostane-type, and three ergostane-type steroids from the fruiting bodies of Pleurotus cornucopiae var. citrinopileatus. The structure of (22Z)-3β,5α,11-trihydroxy-9,11-secoergosta-7,22-diene-6,9-dione, previously reported, have been revised to (22E).

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Sets of spikes emitted sequentially across neurons constitute fundamental pulse packets in neural information processing, including offline memory replay during hippocampal sharp-wave ripples (SWRs). The relative timing of neuronal spikes is fine-tuned in each spike sequence but can vary between different sequences. However, the microcircuitry mechanism that enables such flexible spike sequencing remains unexplored.

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GABAergic neurons are classified into multiple subtypes based on morphology, physiological properties, and gene expression profiles. Although traditionally defined axo-axonic cells (AACs) are a unique type of interneuron that expresses parvalbumin and innervates the axon initial segment (AIS) of pyramidal neurons, a genetic marker for AACs in the basolateral amygdala (BLA) has not been identified. Here, we show that vasoactive intestinal peptide receptor 2 (Vipr2)-expressing interneurons exhibit anatomical and electrophysiological properties of AACs in the BLA.

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The presubiculum, a subarea of the parahippocampal region, plays a critical role in spatial navigation and spatial representation. An outstanding aspect of presubicular spatial codes is head-direction selectivity of the firing of excitatory neurons, called head-direction cells. Head-direction selectivity emerges before eye-opening in rodents and is maintained in adulthood through neurophysiological interactions between excitatory and inhibitory neurons.

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The basolateral amygdala (BLA), a region critical for emotional processing, is the limbic hub that is connected with various brain regions. BLA neurons are classified into different subtypes that exhibit differential projection patterns and mediate distinct emotional behaviors; however, little is known about their presynaptic input patterns. In this study, we employed projection-specific monosynaptic rabies virus tracing to identify the direct monosynaptic inputs to BLA subtypes.

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Structural elucidation and molecular scrutiny of cerebral vasculature is crucial for understanding the functions and diseases of the brain. Here, we introduce SeeNet, a method for near-complete three-dimensional visualization of cerebral vascular networks with high signal-to-noise ratios compatible with molecular phenotyping. SeeNet employs perfusion of a multifunctional crosslinker, vascular casting by temperature-controlled polymerization of hybrid hydrogels, and a bile salt-based tissue-clearing technique optimized for observation of vascular connectivity.

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Genetic manipulation of protein levels is a promising approach to identify the function of a specific protein in living organisms. Previous studies demonstrated that the auxin-inducible degron strategy provides rapid and reversible degradation of various proteins in fungi and mammalian mitotic cells. In this study, we employed this technology to postmitotic neurons to address whether the auxin-inducible degron system could be applied to the nervous system.

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A 2 : 1 hydrogen-bonded crystal of 2-pyrrolidone and chloranilic acid shows structural phase transitions accompanied by the drastic rearrangement of hydrogen-bonded tapes. Such a phenomenon is attributed to the selective and directional character of hydrogen bonds.

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Gamma oscillations within the cerebral cortex and hippocampus are associated with cognitive processes, including attention, sensory perception, and memory formation; a deficit in gamma regulation is a common symptom of neurologic and psychiatric disorders. Accumulating evidence has suggested that gamma oscillations result from the synchronized activity of cell assemblies coordinated mainly by parvalbumin-positive inhibitory interneurons. The modulator molecules for parvalbumin-positive interneurons are major research targets and have the potential to control the specific oscillatory rhythm and behavior originating from neural coordination.

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Perineuronal nets (PNNs) are distributed primarily around inhibitory interneurons in the hippocampus, such as parvalbumin-positive interneurons. PNNs are also present around excitatory neurons in some brain regions and prevent plasticity in these neurons. A recent study demonstrated that PNNs also exist around mouse hippocampal pyramidal cells, which are the principle type of excitatory neurons, in the CA2 subregion and modulate the excitability and plasticity of these neurons.

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Perineuronal nets (PNNs), proteoglycan-rich extracellular matrix structures, are thought to be expressed around inhibitory neurons and contribute to critical periods of brain function and synaptic plasticity. However, in some specific brain regions such as the amygdala, PNNs were predominantly expressed around excitatory neurons. These neurons were recruited during auditory fear conditioning and memory retrieval.

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