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Hirota, M.

Publications and source records attributed to Hirota, M..

6 recordsLinked to original sources

Pathway-Centric Integration of CRISPR Fitness with Molecular Features Draws Cancer State Maps

Cancer cells display heterogeneous pathway activity that shapes therapeutic vulnerability, but mapping it remains challenging. Transcriptomic scores do not directly measure functional activity, and CRISPR knockout data alone lack molecular interpretability. We introduce StateMap, a pathway-centric framework integrating gene expression and genome-wide CRISPR knockout fitness data from the Cancer Dependency Map. For a given pathway, StateMap selects features by co-dependency and mutual information, then projects cell lines into a low-dimensional space reflecting pathway activity and molecular state. Applied to the Hippo pathway, it resolved five functional states refining the YAP-on/YAP-off dichotomy. Notably, the Hippo-strong state showed selective dependence on integrin V{beta}5; ITGAV depletion triggered Hippo-dependent cell aggregation and G1 arrest via enhanced cell-cell adhesion. Machine learning transfer to TCGA identified a matching subtype with poor prognosis, nominated NNMT as a biomarker, and predicted sensitivity to the V inhibitor Cilengitide. StateMap enables pathway-specific state mapping and discovery of state-selective therapeutic vulnerabilities.

cancer biology↗

Delineating JunB's Crucial Function in Mature Th17 Cells through Inducible Targeted Protein Degradation

The AP-1 transcription factor JunB is essential for the differentiation of pathogenic T helper 17 (Th17) cells, which are key mediators of autoimmune diseases such as multiple sclerosis and colitis. While the importance of JunB during Th17 polarization is known, its role in mature Th17 cells--critical therapeutic targets in these diseases--remains unclear. In this study, we employed the dTAG system, a targeted protein degradation approach, to deplete JunB in Th17 cells generated both in vitro and in vivo. During pathogenic Th17 cell differentiation, JunB degradation replicated known effects of JunB deficiency, including reduced expression of interleukin (IL)-17A and the genes encoding ROR{gamma}t (Rorc) and the IL-23 receptor (Il23r). In contrast, in mature pathogenic Th17 cells, JunB degradation downregulated Il23r without affecting IL-17A or Rorc expression. Furthermore, JunB degradation compromised the viability of mature pathogenic Th17 cells. Transcriptomic analyses revealed that JunB regulates distinct gene sets during Th17 polarization compared to mature Th17 cells. The gene Inhba, which encodes activin A, was identified as a JunB target in both stages. Supplementation with activin A restored IL-17A and Rorc expression during pathogenic Th17 cell differentiation. These findings demonstrate that JunB maintains mature pathogenic Th17 cell phenotypes, including IL-23 receptor expression, and supports pathogenic Th17 cell survival. As IL-23 signaling is crucial for sustaining pathogenic Th17 cells, targeting JunB may offer a therapeutic strategy to limit Th17-driven autoimmune inflammation.

immunology↗

Biofluorescence reveals hidden patterns in chitons with implications to visual ecology.

Biofluorescence is apparently widespread in the tree of life. Fluorescence has the potential to contribute to the totality of light leaving an organisms surface and will therefore circumscribe how an individual could be detected and discriminated by their visual predators. Here, we: (i) documented the first record of biofluorescence on polyplacophorans, (ii) spectrally characterized the biofluorescence on shells of living chitons, (iii) measured the colour patch pattern variation, (iv) separated the colour of their shells into their reflectance and fluorescence components, and (v) combined these data with field measurements to calculate perceptual distance in chromatic and achromatic contrasts based on the visual system of their major visually guided predators. We found a red biofluorescence that enhances the brightness of chiton shells, along with a correlation showing that as individuals grow larger, the fluorescing surface area becomes smaller. Our visual models suggest that fluorescence decreases the achromatic contrast of chitons against their naturally fluorescent substrates for most visual predators, making them less noticeable to specific predators. Our results support the potential visual functionality of biofluorescence and open new hypotheses regarding its ecological roles to further investigations.

ecology↗

Human immune and gut microbial parameters associated with inter-individual variations in COVID-19 mRNA vaccine-induced immunity

COVID-19 mRNA vaccines induce protective adaptive immunity against SARS-CoV-2 in most individuals, but there is wide variation in levels of vaccine-induced antibody and T-cell responses. However, factors associated with this inter-individual variation remain unclear. Here, using a systems biology approach based on multi-omics analyses of human blood and stool samples, we find that baseline expression of AP-1 transcription factors, FOS and ATF3, is inversely correlated with BNT162b2 mRNA vaccine-induced T-cell responses. FOS expression is associated with transcription modules related to baseline immunity, but it is negatively associated with those related to T-cell activation upon BNT162b2 mRNA stimulation. Interestingly, the gut microbial fucose/rhamnose degradation pathway is positively correlated with FOS and ATF3 expression and inversely correlated with BNT162b2-induced T-cell responses. Taken together, these results demonstrate that baseline expression of AP-1 genes, which is associated with the gut microbial fucose/rhamnose degradation pathway, is a key negative correlate of BNT162b2-induced T-cell responses.

immunology↗

ssDNA is not superior to dsDNA as long HDR donors for CRISPR-mediated endogenous gene tagging in human diploid cells

Recent advances in CRISPR technology have enabled us to perform gene knock-in in various species and cell lines. CRISPR-mediated knock-in requires donor DNA which serves as a template for homology-directed repair (HDR). For knock-in of short sequences or base substitutions, ssDNA donors are frequently used among various other forms of HDR donors, such as linear dsDNA. However, for insertion of long transgenes such as fluorescent reporters in human cells, the optimal type of HDR donors remains unclear. In this study, we established a simple and efficient CRISPR-mediated knock-in method for long transgenes using linear dsDNA and ssDNA donors, and systematically compared the performance of these two donors for endogenous gene tagging in human non-transformed diploid cells. Quantification using flow cytometry revealed higher efficiency of fluorescent tagging with dsDNA donors than with ssDNA. By analyzing knock-in outcomes using long-read amplicon sequencing and a classification framework, a variety of mis-integration events were detected regardless of the donor type. Importantly, the ratio of precise insertion was higher with dsDNA donors than with ssDNA. Moreover, in off-target integration analyses, dsDNA and ssDNA were comparably prone to non-homologous integration. These results indicate that ssDNA is not superior to dsDNA as long HDR donors for gene knock-in in human cells.

cell biology↗

Mucin O-glycans facilitate symbiosynthesis to maintain gut immune homeostasis

The dysbiosis of gut microbiota has been implicated in the pathogenesis of inflammatory bowel diseases (IBDs); however, the underlying mechanisms have not yet been elucidated. Heavily glycosylated mucin not only establishes a first-line barrier against pathogens, but also serves as a niche for microbial growth. We hypothesized that dysbiosis may cause abnormal mucin utilization and microbial metabolic dysfunction. To test this hypothesis, we analyzed short-chain fatty acids (SCFAs) and mucin components in the stool samples of 40 healthy subjects, 49 ulcerative colitis (UC) patients, and 44 Crohns disease (CD) patients from Japan. The levels of n-butyrate were significantly lower in the stools of both the CD and UC patients than in those of the healthy subjects. Correlation analysis identified 7 bacterial species positively correlated with n-butyrate levels, among which the major n-butyrate producer, Faecalibacterium prausnitzii, was particularly underrepresented in CD patients, but not in UC patients. In UC patients, there were inverse correlations between mucin O-glycan levels and the production of SCFAs, such as n-butyrate, suggesting that mucin O-glycans act as an endogenous fermentation substrate for n-butyrate production. Indeed, mucin-fed rodents exhibited enhanced n-butyrate production, leading to the expansion of RORgt+Treg cells and IgA-producing cells in the colonic lamina propria. Importantly, the availability of mucin-associated O-glycans to the microbiota was significantly reduced in n-butyrate-deficient UC patients. Taken together, our findings highlight the biological significance of the symbiosynthesis pathway in the production of n-butyrate, which maintains gut immune homeostasis.

microbiology↗