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Wada, M.

Publications and source records attributed to Wada, M..

10 recordsLinked to original sources

Postmortem Alterations of Metabotropic Glutamate Receptors across Neuropsychiatric Disorders: A Systematic Review

Metabotropic glutamate receptors (mGluRs) regulate glutamatergic transmission and have been implicated in diverse neuropsychiatric disorders, but human postmortem evidence remains fragmented. We aimed to map these findings across diagnoses, receptor subtypes, brain regions, and measurement modalities. Following PRISMA guidelines, we systematically searched MEDLINE, EMBASE, and Web of Science from inception to August 8, 2026, for studies assessing GRM transcripts, as well as mGluR protein abundance, localization, assembly, or receptor binding in human postmortem brain tissue. Of 532 records identified, 57 reports met eligibility criteria. Findings were synthesized narratively because of substantial heterogeneity in diagnoses, brain regions, receptor subtypes, and assays. Postmortem evidence was concentrated on mGluR5, mGluR2/3, and mGluR1, and on the prefrontal cortex, anterior cingulate cortex, and hippocampus. mGluR-related alterations were reported across disorders, including schizophrenia, major depressive disorder, Alzheimer disease, autism spectrum disorder, and alcohol use disorder. Although most analyses yielded null findings, the direction and magnitude of mGluR alterations varied across brain regions, receptor subtypes, and molecular endpoints. This inconsistency may partly reflect the distinct biological levels captured by transcript abundance, total protein, receptor assembly, localization, and ligand binding, together with regional, cell-type, disease-stage, and clinical heterogeneity. The available evidence therefore suggests context-dependent alterations in mGluR biology but not a uniform or disorder-specific molecular signature. Integration of postmortem findings with other approaches, including in vivo imaging, may clarify their biological and clinical significance.

neuroscience↗

SAM-Targeted CRISPR-Cas9 RNP Delivery Combined with Leaf Regeneration Enables DNA-Free, Non-Chimeric Genome Editing in 'Fuji' Apple

DNA-free genome editing is a promising strategy for the genetic improvement of horticultural crops and fruit trees because it enables targeted mutagenesis without stable genetic transformation. In planta particle bombardment (iPB) delivers CRISPR-Cas9 ribonucleoproteins (RNPs) directly into shoot apical meristems (SAMs), enabling heritable genome editing without the use of tissue culture-based transformation systems. However, the practical application of iPB-mediated editing in fruit trees is limited by the frequent occurrence of chimerism, which cannot be readily eliminated through sexual segregation while maintaining the genetic background of elite cultivars. To overcome this limitation, we combined iPB-mediated RNP delivery with regeneration from edited leaf tissues (iPB-REG). Using this approach, we targeted the self-incompatibility gene S9-RNase in the elite apple cultivar Fuji and efficiently recovered non-chimeric edited plants. These results establish iPB-REG as a practical strategy for producing uniform genome-edited fruit trees and provide a valuable platform for DNA-free genetic improvement and functional genomics in clonally propagated perennial crops.

plant biology↗

Co-targeting an AMPK--MAPK axis reprograms CAFs and suppresses PDAC

Pancreatic ductal adenocarcinoma (PDAC) is a fatal cancer characterized by limited therapeutic options and a highly treatment-resistant tumor microenvironment. Beyond tumor-intrinsic genetic alterations, growing evidence indicates that host-microbiome interactions influence cancer progression through microbial metabolites. However, how microbiome-derived metabolites influence oncogenic signaling in PDAC remains unclear. Here, integrated profiling revealed a consistent reduction of the microbial metabolite acetic acid in fecal samples from treatment-naive patients with PDAC and in a genetically defined Drosophila model recapitulating key PDAC driver alterations. Acetic acid activates AMP-activated protein kinase, and pharmacological activation of this pathway together with inhibition of mitogen-activated protein kinase signaling suppressed tumor growth in fly and mouse models. Combined pathway targeting restored AMPK activity and suppressed cancer-associated fibroblast activation. These findings identify a microbiome-associated metabolic vulnerability in PDAC and suggest that coordinated targeting of metabolic and oncogenic signaling may restrain tumor progression and improve therapeutic strategies.

cancer biology↗

Maternal care during early development is necessary for the acquisition of a calming response to back stroking

In many mammals, early postnatal interactions between caregivers and offspring involve rich physical contact, including stroking, holding, and grooming. Offspring typically remain calm and close to the caregiver during such stimulation. Although these behaviors are thought to support emotional regulation and bonding during infancy, the underlying mechanisms and the role of prior experience remain unclear. Here, we demonstrate that back stroking induces a conserved calming response in both human infants and mouse pups, characterized by reduced movement and heart rate. In mouse pups, stroking further facilitated sleep onset, increased EEG delta power, and attenuated stress-induced corticosterone elevations. These sleep-promoting and stress-buffering effects were absent in artificially reared pups deprived of postnatal maternal contact, underscoring the importance of early tactile experience. Transcriptomic analysis revealed downregulation of the voltage-gated calcium channel subunit gene Cacna1b in the hypothalamus of artificially reared pups. Moreover, knockdown of hypothalamic Cacna1b in maternally reared pups abolished stroking-induced calming and sleep-promoting effects. This study identifies a conserved, experience-dependent calming response to affiliative tactile input, biologically embedded through plasticity, that supports physiological regulation and stress resilience during early development. Our results highlight that affiliative tactile sensation, like discriminative tactile sensation, depends on early experience to organize neural mechanisms regulating internal states. SignificanceEarly-life physical contact with caregivers is essential for healthy emotional and physiological development in mammals, but its underlying mechanisms remain unclear. We show that back stroking induces a conserved calming response in both human infants and mouse pups, reducing movement, heart rate, and promoting sleep. These effects depend on early tactile experience and are mediated by Cacna1b expression in the hypothalamus. Our findings identify a plastic, experience-dependent pathway through which affiliative tactile input modulates internal states, revealing how parental care supports stress resilience and sleep physiology during early development.

neuroscience↗

Validation of EEG data assimilation-based prefrontal excitation-inhibition balance estimation using TMS-EEG

The excitation and inhibition (E/I) balance of neural circuits is a crucial index reflecting neurophysiological homeostasis. Although several cutting-edge methods have been established to assess E/I balance in an intact brain, they have inherent limitations, such as difficulties in tracking changes in E/I balance over time. To tackle this issue, we have proposed neural-mass-model-based tracking of the brain states using a data assimilation (DA) scheme in our previous work. However, although we verified that sleep-dependent changes in E/I balance can be estimated from electroencephalography data, the neurophysiological validity of the method was not evaluated. Therefore, in the current study, we directly compared estimated E/I states based on the DA methods with the concurrent transcranial magnetic stimulation and electroencephalography (TMS-EEG) based methods. The results showed that the E/I changes estimated by the DA-based method correlated significantly with E/I in the dorsolateral prefrontal cortex, as indexed by TMS-evoked EEG. These findings indicate that our proposed method can estimate neurophysiologically valid changes in E/I balance.

neuroscience↗

The Translation Termination Factor eRF3 Interacts Sequentially with eRF1 and ABCE1 on the Ribosome

To elucidate the molecular mechanisms connecting translation termination and ribosome recycling, interactions among eRF1, eRF3, and ABCE1, were genetically investigated in Saccharomyces cerevisiae. Heterologous factors from Pneumocystis carinii and humans, along with their mutants were successfully used for co-functional studies in conditional double knockout, double tetOFF strains. Combination of P. carinii eRF3 mutants with S. cerevisiae eRF1 and ABCE1 revealed that all the eRF3 mutants co-functioned with eRF1, but exhibited varying interactions with ABCE1 depending on the mutants. These findings provide evidence that eRF3 remains bound to the GTPase center of the ribosome, awaiting ABCE1. Thus, eRF3 sequentially interacts with eRF1 and ABCE1 during the final steps of translation.

genetics↗

PURIFICATION METHOD FOR ADENO-ASSOCIATED VIRAL VECTOR SEROTYPE 9 USING CERAMIC HYDROXYAPATITE CHROMATOGRAPHY AND ITS QUALIFICATION

Adeno-associated virus (AAV) vectors can efficiently transduce exogenous genes into various tissues in vivo. Owing to their convenience, high efficiency, long-term stable gene expression, and minimal side effects, AAV vectors have become one of the gold standards for investigating gene functions in vivo, especially in non-clinical studies. However, challenges persist in efficiently preparing a substantial quantity of high-quality AAV vectors that comprise only genome-packaged full particles. Commercial AAV vectors are typically associated with high costs. Further, in-laboratory production is hindered by the lack of specific laboratory equipment, such as ultracentrifuges. Therefore, a simple, quick, and scalable preparation method for AAV vectors is needed for proof-of-concept experiments. Herein, we present an optimized method for producing and purifying high-quality AAV serotype 9 (AAV9) vectors using standard laboratory equipment and chromatography. Using ceramic hydroxyapatite as a mixed-mode chromatography medium can markedly increase the quality of purified AAV vectors. Basic protocols and optional methods for evaluating purified AAV vectors are also described.

molecular biology↗

Cysteine restriction induces ferroptosis depending on the polyamine biosynthetic pathway in hepatic cancer cells

Background and AimsMetabolic activities are also known to affect responses and disease processes of the liver which is a central organ for organismal metabolism. Liver diseases such as intestinal failure associated liver disease (IFALD) and hepatocellular carcinoma are known to be affected by nutrition contents, but the mechanisms behind them remain unclear. In this study, we aimed to reveal the relationship between the concentration of sulfur-containing amino acids and hepatocellular response, and further investigated the mechanism focusing on methionine adenosyltransferase (MAT), which plays the central role in methionine metabolism by synthesizing S-adenosylmethionine (SAM). MethodsMouse hepatoma Hepa1 cells were cultured in media with reduced amounts of cysteine, methionine, or both. Cell death was monitored using propidium iodide (PI) and annexin V staining followed by flow cytometry. Inhibitors of ferroptosis (Fer-1), autophagy (GSK872), SAM synthesis (cycloleucine), or polyamine synthesis (sardomozide and DFMO) were used. ResultsCysteine restriction induced marked cell death, whereas simultaneous restriction of cysteine and methionine fully suppressed the cell death. Cysteine restriction-induced cell death was suppressed with Fer-1 and GSK872, suggesting the involvement of ferroptosis in this process. Cysteine restriction-induced cell death was also suppressed by knockdown of MAT2A or its inhibitor cycloleucine. Furthermore, inhibitors of several enzymes in the polyamine biosynthetic pathway also suppressed the cell death. In contrast, primary culture of mouse hepatocytes did not show cell death upon cysteine restriction. ConclusionsThese results suggest that SAM-polyamine metabolism is a critical modulator of ferroptosis of hepatic cancer cells. Since normal liver cells were more resistant to ferroptosis than cancer cells, cysteine restriction may be exploited in treating hepatic cancer by inducing ferroptosis specifically in cancer cells without affecting normal cells in the liver. Graphical abstrct O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=61 SRC="FIGDIR/small/582667v1_ufig1.gif" ALT="Figure 1"> View larger version (13K): org.highwire.dtl.DTLVardef@bcb32borg.highwire.dtl.DTLVardef@96d39corg.highwire.dtl.DTLVardef@1eaa25org.highwire.dtl.DTLVardef@1346f82_HPS_FORMAT_FIGEXP M_FIG C_FIG

biochemistry↗

Cryo-EM structure of the MgtE Mg2+ channel pore domain in Mg2+-free conditions reveals cytoplasmic pore opening

MgtE is a Mg2+ channel conserved in organisms ranging from prokaryotes to eukaryotes, including humans, and plays an important role in Mg2+ homeostasis. The previously determined MgtE structures in the Mg2+-bound, closed state and structure-based functional analyses of MgtE revealed that the binding of Mg2+ ions to the MgtE cytoplasmic domain induces channel inactivation to maintain Mg2+ homeostasis. However, due to the lack of a structure of the MgtE channel, including its transmembrane domain in Mg2+-free conditions, the pore-opening mechanism of MgtE has remained unclear. Here, we determined the cryoelectron microscopy (cryo-EM) structure of the MgtE-Fab complex in the absence of Mg2+ ions. The Mg2+-free MgtE transmembrane domain structure and its comparison with the Mg2+-bound, closed-state structure, together with functional analyses, showed the Mg2+-dependent pore opening of MgtE on the cytoplasmic side and revealed the kink motions of the TM2 and TM5 helices at the glycine residues, which are important for channel activity. Overall, our work provides structure-based mechanistic insights into the channel gating of MgtE.

biophysics↗

CHLOROPLAST UNUSUAL POSITIONING 1 is a new type of actin nucleation factor in plants

Plants have evolved unique responses to fluctuating light conditions in their environment. One such response, chloroplast photorelocation movement, optimizes photosynthesis under weak light and prevents photodamage under strong light. CHLOROPLAST UNUSUAL POSITIONING 1 (CHUP1) plays a pivotal role in the light-responsive chloroplast movements, which are driven by dynamic reorganization of chloroplast actin (cp-actin) filaments. In this study, we demonstrated that fluorescently tagged CHUP1 colocalized and was coordinately reorganized with cp-actin filaments during chloroplast movement in Arabidopsis thaliana. The resulting asymmetric distribution of CHUP1 was reversibly regulated by the blue light receptor phototropin. X-ray crystallography indicated that the CHUP1 C-terminal domain shares structural similarity with the formin homology 2 (FH2) domain, although there is no sequence similarity between the two domains. The CHUP1 C-terminal domain stimulated actin polymerization in the presence of profilin. We conclude that CHUP1 is a novel, plant-specific actin nucleator that functions in cp-actin-based chloroplast movement. HighlightsO_LIBlue light changes the distribution pattern of CHUP1 C_LIO_LIFormin FH2 and CHUP1 C-terminal domains are structurally similar but not homologous C_LIO_LICHUP1 nucleates and severs actin filaments in vitro C_LIO_LICHUP1 is a novel, plant-specific actin nucleator for chloroplast movement C_LI

plant biology↗