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Hasegawa, Y.

Publications and source records attributed to Hasegawa, Y..

At least 37 records · Page 2Linked to original sources

Global changes in open reading frame dominance of RNAs during cancer initiation and progression

Cancer cells express unique RNA transcripts; however, the factors determining their translation have remained unclear. We recently developed open reading frame (ORF) dominance as a measure that correlates with coding potential of RNAs. Upon calculating the ORF dominance of cancer-specific transcripts across 24 human tumor types, 14 exhibited significantly higher ORF dominance in cancer than in normal tissues. In organoid-based mouse genetic models, ORF dominance increased with carcinogenesis. Gene ontology analysis revealed that gene sets with increased ORF dominance were associated with cell proliferation, while those with decreased ORF dominance were linked to DNA damage response. Translatome analyses demonstrated that elevated ORF dominance during carcinogenesis resulted in higher translation frequencies of ribosome-bound RNAs. As cancer progressed, ORF dominance showed that the boundary between coding and noncoding transcripts became blurred prior to distant metastasis, indicating decreased proliferative cell populations and increased generation of RNA isoforms that potentially translate neoantigens before the development of metastatic tumors. These findings suggest that cancer evolution leads to dynamic changes in ORF dominance, resulting in global translational alterations in transcriptomes.

cancer biology↗

Peripheral serotonergic neurons regulate anxiety-like behavior and intestinal barrier immunity

Serotonergic circuits in the central nervous system play important roles in regulating mood and behavior, yet the functions of peripheral serotonergic neurons are less understood. Here, we engineered mice lacking the serotonin-producing enzyme Tph2 in peripheral neurons but with intact Tph2 in central neurons. In contrast to mice lacking Tph2 in all neurons, mice lacking Tph2 in peripheral serotonergic neurons did not exhibit increased territorial aggression. However, similar to the total body Tph2 KO mice, the conditional KO animals, exhibited reduced gut motility and decreased anxiety-like behavior. These observations reveal that peripheral serotonergic neurons contribute to control of intestinal motility and anxiety-like behavior and suggest that therapeutics targeting this subset of peripheral neurons could be beneficial.

immunology↗

A bile metabolite atlas reveals infection-triggered interorgan mediators of intestinal homeostasis and defense

An essential function of the liver is the formation of bile. This aqueous solution is critical for fat absorption and is transported to the duodenum via the common bile duct. Despite extensive studies of bile salts, other components of bile are less well-charted. Here, we characterized the murine bile metabolome and investigated how the microbiota and enteric infection influence bile composition. We discovered that the bile metabolome is not only substantially more complex than appreciated but is dynamic and responsive to the microbiota and enteric infection. Hepatic transcriptomics identified enteric infection-triggered pathways that likely underlie bile remodeling. Enteric infections stimulated elevation of four dicarboxylates in bile that modulated intestinal gut epithelial and microbiota composition, inflammasome activation, and host defense. Our data suggest that enteric infection-associated signals are relayed between the intestine and liver and induce transcriptional programs that shape the bile metabolome, modifying biles immunomodulatory and host defense functions.

microbiology↗

Pulmonary osteoclast-like cells in silica induced pulmonary fibrosis

The pathophysiology of silicosis is poorly understood, limiting development of therapies for those who have been exposed to the respirable particle. We explored the mechanisms of silica-induced pulmonary fibrosis in a mouse model using multiple modalities including wholelung single-nucleus RNA sequencing. These analyses revealed that in addition to pulmonary inflammation and fibrosis, intratracheal silica challenge induced osteoclast-like differentiation of alveolar macrophages and recruited monocytes, driven by induction of the osteoclastogenic cytokine, receptor activator of nuclear factor-{kappa}B ligand (RANKL) in pulmonary lymphocytes and alveolar type II cells. Furthermore, anti-RANKL monoclonal antibody treatment suppressed silica-induced osteoclast-like differentiation in the lung and attenuated silica-induced pulmonary fibrosis. We conclude that silica induces osteoclast-like differentiation of distinct recruited and tissue resident monocyte populations, leading to progressive lung injury, likely due to sustained elaboration of bone resorbing proteases and hydrochloric acid. Interrupting osteoclast-like differentiation may therefore constitute a promising avenue for moderating lung damage in silicosis. One Sentence SummarySilica induces the alveolar epithelium to reprogram recruited and resident pulmonary myeloid cells to become osteoclasts that contribute to pulmonary fibrosis.

pathology↗

Immune-related molecular changes in the olfactory epithelium, structural alteration in the olfactory bulb, and psychosis

Smell deficits and neurobiological changes in the olfactory bulb (OB) and olfactory epithelium (OE) have been observed in schizophrenia and related disorders. The OE is the most peripheral olfactory system located outside the cranium, and is connected with the brain via direct neuronal projections to the OB. Nevertheless, it is unknown whether and how a disturbance of the OE affects the OB in schizophrenia and related disorders. Addressing this gap would be the first step in studying the impact of OE pathology in the disease pathophysiology in the brain. In this cross-species study, we observed that chronic, local OE inflammation with a set of upregulated genes in an inducible olfactory inflammation (IOI) mouse model led to a volume reduction, layer structure changes, and alterations of neuron functionality in the OB. Furthermore, IOI model also displayed behavioral deficits relevant to negative symptoms (avolition) in parallel to smell deficits. In first episode psychosis (FEP) patients, we observed a significant alteration in immune/inflammation-related molecular signatures in olfactory neuronal cells (ONCs) enriched from biopsied OE and a significant reduction in the OB volume, compared with those of healthy controls (HC). The increased expression of immune/inflammation-related molecules in ONCs was significantly correlated to the OB volume reduction in FEP patients, but no correlation was found in HCs. Moreover, the increased expression of human orthologues of the IOI genes in ONCs was significantly correlated with the OB volume reduction in FEP, but not in HCs. Together, our study implies a potential mechanism of the OE-OB pathology in patients with psychotic disorders (schizophrenia and related disorders). We hope that this mechanism may have a cross-disease implication, including COVID-19-elicited mental conditions that include smell deficits.

molecular biology↗

A single-cell atlas of bobtail squid visual and nervous system highlights molecular principles of convergent evolution

Although the camera-type eyes of cephalopods and vertebrates are a canonical example of convergent morphological evolution, the cellular and molecular mechanisms underlying this convergence remain obscure. We used genomics and single cell transcriptomics to study these mechanisms in the visual system of the bobtail squid Euprymna berryi, an emerging cephalopod model. Analysis of 98,537 cellular transcriptomes from the squid visual and nervous system identified dozens of cell types that cannot be placed in simple correspondence with those of vertebrate or fly visual systems, as proposed by Ramon y Cajal and J.Z. Young. Instead, we find an unexpected diversity of neural types, dominated by dopamine, and previously uncharacterized glial cells. Surprisingly, we observe changes in cell populations and neurotransmitter usage during maturation and growth of the visual systems from hatchling to adult. Together these genomic and cellular findings shed new light on the parallel evolution of visual system complexity in cephalopods and vertebrates.

evolutionary biology↗

Single-nucleotide substitution determines pollen production in Japanese cedar

Pollinosis, also known as pollen allergy or hay fever, is a global problem caused by pollen produced by various plant species1-6. The wind-pollinated Japanese cedar (Cryptomeria japonica) is the largest contributor to severe pollinosis in Japan, where increasing proportions of people have been affected in recent decades7. The MS4 (MALE STERILITY 4) locus of Japanese cedar controls pollen production, and its homozygous mutants (ms4/ms4) show abnormal pollen development after the tetrad stage and produce no mature pollen. In this study, we narrowed down the MS4 locus by fine mapping in Japanese cedar and found TKPR1 (TETRAKETIDE -PYRONE REDUCTASE) gene in this region. Transformation experiments using Arabidopsis thaliana showed that single-nucleotide substitution of CjTKPR1 determines pollen production. Broad conservation of TKPR1 beyond plant division could lead to the creation of pollen-free plant not only for Japanese cedar but also for broader plant species.

plant biology↗

Multi-omic brain and behavioral correlates of cell-free fetal DNA methylation in macaque maternal obesity models

Maternal obesity during pregnancy is associated with neurodevelopmental disorder (NDD) risk. We utilized integrative multi-omics to examine maternal obesity effects on offspring neurodevelopment in rhesus macaques by comparison to lean controls and two interventions. Differentially methylated regions (DMRs) from longitudinal maternal blood-derived cell-free fetal DNA (cffDNA) significantly overlapped with DMRs from infant brain. The DMRs were enriched for neurodevelopmental functions, methylation-sensitive developmental transcription factor motifs, and human NDD DMRs identified from brain and placenta. Brain and cffDNA methylation levels from a large region overlapping mir-663 correlated with maternal obesity, metabolic and immune markers, and infant behavior. A DUX4 hippocampal co-methylation network correlated with maternal obesity, infant behavior, infant hippocampal lipidomic and metabolomic profiles, and maternal blood measurements of DUX4 cffDNA methylation, cytokines, and metabolites. Ultimately, maternal obesity altered infant brain and behavior, and these differences were detectable in pregnancy through integrative analyses of cffDNA methylation with immune and metabolic biomarkers.

genomics↗

Novel insights into pulmonary phosphate homeostasis and osteoclastogenesis emerge from the study of pulmonary alveolar microlithiasis.

Pulmonary alveolar microlithiasis (PAM) is an autosomal recessive lung disease caused by a deficiency in the pulmonary epithelial Npt2b sodium-phosphate co-transporter that results in accumulation of phosphate and formation of hydroxyapatite microliths in the alveolar space. The single cell transcriptomic analysis of a PAM lung explant showing a robust osteoclast gene signature in alveolar monocytes and the finding that calcium phosphate microliths contain a rich protein and lipid matrix that includes bone resorbing osteoclast enzymes suggested a role for osteoclast-like cells in the defense against microliths. While investigating the mechanisms of microlith clearance, we found that Npt2b modulates pulmonary phosphate homeostasis through effects on alternative phosphate transporter activity and alveolar osteoprotegerin, and that microliths induce osteoclast formation and activity in a receptor activator of nuclear factor-{kappa}B ligand (RANKL) and dietary phosphate dependent manner. This work reveals that Npt2b and pulmonary osteoclast-like cells play key roles in pulmonary homeostasis and suggest potential new therapeutic targets for the treatment of lung disease.

molecular biology↗

Escaping through the predator's gill cleft: A defensive tactic of juvenile eels after capture by predatory fish

Some prey animals can actively escape from predators even after being captured, but knowledge of such behaviors is still limited, especially in vertebrates. Here, we report the unique active escape behavior of Japanese eel Anguilla japonica juveniles through the gill cleft of the predatory fish Odontobutis obscura. Of the 54 A. japonica juveniles captured by the predator, 28 escaped via the predators gill, and most escaped individuals survived afterwards. In all escaped individuals, their tails emerged first from the gill cleft of the predator, and then their whole bodies slipped out in a backward direction from the cleft. These findings indicate that A. japonica juveniles have the specialized antipredator tactic, which provides the basis for further investigation from behavioral, ecological, and evolutionary perspectives.

zoology↗

Mutational effects of ubiquitously present gamma radiation on Arabidopsis thaliana: insight into radiosensitivity in the reproductive stage

Earth has always been exposed to ionizing radiation from natural sources, and man-made sources have added to this radiation. In order to assess mutational effects of ubiquitously present radiation on plants, we performed a whole-genome resequencing analysis of mutations induced by chronic irradiation throughout the life-cycle of Arabidopsis thaliana under controlled conditions. Resequencing data from 12 M1 lines and 36 M2 progeny derived under gamma-irradiation conditions ranging from 0.0 to 2.0 Gy/d were obtained to identify de novo mutations, including single base substitutions (SBSs) and small insertions/deletions (INDELs). The relationship between de novo mutation frequency and a low-to-middling dose of radiation was assessed by statistical modeling. The increasing of de novo mutations in response to doses of irradiation fit the negative binomial model, accounting for the high variability of mutation frequency observed. Among the different types of mutations, SBSs were more prevalent than INDELs, with deletions being more frequent than insertions. Furthermore, we observed that the mutational effects of chronic radiation are more intensive during the reproductive stage. These outcomes could provide valuable insights into practical strategies for environmental radioprotection of plants on Earth and in space.

genetics↗

Different SP1 binding dynamics at individual genomic loci in human cells

Using a tamoxifen-inducible time-course ChIP-seq approach, we show that the ubiquitous transcription factor SP1 has different binding dynamics at its target sites in the human genome that are not correlated with SP1 occupancy levels at those sites. While ~70% of SP1 binding sites are located in promoter regions, loci with slow SP1 binding turnover are enriched in enhancer and Polycomb-repressed regions. Unexpectedly, SP1 sites with fast turnover times tend to have higher quality and more copies of the SP1 sequence motif. Different co-binding factors associate near SP1 binding sites depending on their binding kinetics and on their location at promoters or enhancers. For example, NFY and FOS are preferentially associated near promoter-bound SP1 sites with fast turnover, whereas DNA motifs of ETS and homeodomain proteins are preferentially observed at sites with slow turnover. At promoters but not enhancers, proteins involved in sumoylation and PML bodies associate more strongly with slow SP1 binding sites than with the fast-binding sites. The speed of SP1 binding turnover is not associated with nucleosome occupancy, and it is not necessarily coupled to higher transcriptional activity. These results with SP1 are in contrast from those of human TBP, indicating that there is no common mechanism affecting transcription factor binding kinetics.

molecular biology↗

Numerical evaluation reveals the effect of branching morphology on vessel transport properties during angiogenesis

Blood flow governs transport of oxygen and nutrients into tissues. Hypoxic tissues secrete VEGFs to promote angiogenesis during development and in tissue homeostasis. In contrast, tumors enhance pathologic angiogenesis during growth and metastasis, suggesting suppression of tumor angiogenesis could limit tumor growth. In line with these observations, various factors have been identified to control vessel formation in the last decades. However, their impact on the vascular transport properties of oxygen remain elusive. Here, we take a computational approach to examine the effects of vascular branching on blood flow in the growing vasculature. First of all, we reconstruct the 3D vascular model from the 2D confocal images of the growing vasculature at P6 mouse retina, then simulate blood flow in the vasculature, which is applied for the gene targeting mouse models causing hypo- or hyper-branching vascular formation. Interestingly, hyper-branching morphology attenuates effective blood flow at the angiogenic front and promotes tissue hypoxia. In contrast, vascular hypo-branching enhances blood supply at the angiogenic front of the growing vasculature. Oxygen supply by newly formed blood vessels improves local hypoxia and decreases VEGF expression at the angiogenic front during angiogenesis. Consistent with the simulation results indicating improved blood flow in the hypo-branching vasculature, VEGF expression around the angiogenic front is reduced in those mouse retinas. Conversely, VEGF expression was enhanced in the hyper-branching vasculature in the mouse retina. Our results indicate the importance of detailed flow analysis in evaluating the vascular transport properties of branching morphology of the blood vessels. Author SummaryBlood vessels are important for the transport of various substances, such as oxygen, nutrients, and cells, to the entire body. Control of blood vessel formation is thought to be important in health and disease. In the last decades, various factors which regulate blood vessel branching morphology have been identified. Gene modification of some of these identified factors results in hyper-branching of the vasculature while others cause hypo-branching of the vessel. Given the importance of the transport property of the blood vessel, it is important to examine the effect of these identified factors on the transport property of the affected vascular morphology. In line with these facts, we reconstruct 3D vessel structures from 2D confocal microscopy images. We then simulate blood flow in the structures numerically. Interestingly, our results suggest vessel network complexity negatively affects the blood perfusion efficiency and tissue oxygenation during angiogenesis. Thus, our results highlight the importance of flow analysis considering the detailed 3D branching pattern of the vascular network to quantitatively evaluate its transport properties.

developmental biology↗

TGN/EE SNARE protein SYP61 is ubiquitinated and required for carbon/nitrogen-nutrient responses in Arabidopsis

Ubiquitination is a post-translational modification with reversible attachment of the small protein ubiquitin, which is involved in numerous cellular processes including membrane trafficking. For example, ubiquitination of cargo proteins is known to regulate their subcellular dynamics, and plays important roles in plant growth and stress adaptation. However, the regulatory mechanism of the trafficking machinery components remains elusive. Here, we report Arabidopsis trans-Golgi network/early endosome (TGN/EE) localized soluble N-ethylmaleimide sensitive factor attachment protein receptor (SNARE) protein SYP61 as a novel ubiquitination target of a membrane localized ubiquitin ligase ATL31. SYP61 is a key component of membrane trafficking in Arabidopsis. SYP61 was ubiquitinated with K63-linked chain by ATL31 in vitro and in plants. The knockdown mutants of SYP61 were hypersensitive to the disrupted carbon (C)/nitrogen (N)-nutrient stress, suggesting its critical role in plant homeostasis in response to nutrients. We also found the ubiquitination status of SYP61 is affected by C/N-nutrient availability. These results provided possibility that ubiquitination of SNARE protein has important role in plant physiology.

plant biology↗

Marker-assisted selection of trees with MALE STERALITY 1 in Cryptomeria japonica D. Don

Practical use of marker-assisted selection (MAS) is limited in conifers because of the difficulty with developing markers due to a rapid decrease in linkage disequilibrium, the limited genomic information available, and the diverse genetic backgrounds among breeding material collections. First, in this study, two families were produced by artificial crossing between two male-sterile trees, Shindai11 and Shindai12, and a plus tree, Suzu-2 (Ms1/ms1) (S11-S and S12-S families, respectively). The segregation ratio between male-sterile and male-fertile trees did not deviate significantly from the expected 1:1 ratio in either family. These results clearly suggested that the male-sterile gene of Shindai11 and Shindai12 is MALE STERALITY 1 (MS1). Because some markers reported previously have not been linkage mapped, we constructed a partial linkage map of the region encompassing MS1 using the S11-S and S12-S families. For the S11-S and S12-S families, 19 and 18 markers were mapped onto the partial linkage maps of MS1 region, respectively. There was collinearity (conserved gene order) between the two partial linkage maps. Two markers (CJt020762_ms1-1 and reCj19250_2335) were mapped to the same position as the MS1 locus on both maps. Of these markers, we used CJt020762 for MAS in this study. According to the MAS results for 650 trees from six prefectures of Japan (603 trees from breeding materials and 47 trees from the Ishinomaki natural population), five trees in Niigata Prefecture and one tree in Yamagata Prefecture had heterozygous ms1-1, and three trees in Miyagi Prefecture had heterozygous ms1-2. The results obtained in this study suggested that there may be geographical hotspots for the ms1-1 and ms1-2 alleles. Because MAS can be used effectively to reduce the labor and time required for selection of trees with a male-sterile gene, the number of breeding materials should increase in the future.

genetics↗

Development of diagnostic PCR and LAMP markers for MALE STERILITY 1 (MS1) in Cryptomeria japonica D. Don

ObjectiveDue to the allergic nature of the pollen of Cryptomeria japonica, the most important Japanese forestry conifer, a pollen-free cultivar is preferred. Mutant trees detected in nature have been used for the production of a pollen-free cultivar. In order to reduce the time and cost needed for the production and breeding, we aimed to develop simple diagnostic molecular markers for mutant alleles of the causative gene MALE STERILITY 1 (MS1) in C. japonica. The expected function of this gene, its two dysfunctional mutations, and genetic diversity were described recently in a related study. ResultsWe have developed PCR and LAMP markers to detect mutant alleles and to present experimental options depending on available laboratory equipment. At field stations, where PCR machines are not available, LAMP markers were developed. LAMP only needs heat-blocks or a water bath to perform the isothermal amplification and assay results can be easily seen by eye. Because the causative mutations were deletions, two kinds of PCR markers, amplified length polymorphism (ALP) and allele specific PCR (ASP) markers, were developed. These assays can be carried out by capillary or agarose gel electrophoresis.

genetics↗

Identification and genetic diversity analysis of a male-sterile gene (MS1) in Japanese cedar (Cryptomeria japonica D. Don)

Identifying causative genes for a target trait in conifer reproduction is challenging for species lacking whole-genome sequences. In this study, we searched for the male-sterility gene (MS1) in Cryptomeria japonica, aiming to promote marker-assisted selection (MAS) of male-sterile C. japonica to reduce the pollinosis caused by pollen dispersal from artificial C. japonica forests in Japan. We searched for mRNA sequences expressed in male strobili and found the gene CJt020762, coding for a lipid transfer protein containing a 4-bp deletion specific to male-sterile individuals. We also found a 30-bp deletion by sequencing the entire gene of another individual with the ms1. All nine breeding materials with the allele ms1 had either a 4-bp or 30-bp deletion in gene CJt020762, both of which are expected to result in faulty gene transcription and function. Furthermore, the 30-bp deletion was detected from three of five individuals in the Ishinomaki natural forest. From our findings, CJt020762 was considered to be the causative gene of MS1. Thus, by performing MAS using two deletion mutations as a DNA marker, it will be possible to find novel breeding materials of C. japonica with the allele ms1 adapted to the unique environment of each region of the Japanese archipelago.

genetics↗

Cloning of Two Gene Clusters Involved in the Catabolism of 2,4-Dinitrophenol by Paraburkholderia sp. Strain KU-46 and Characterization of the Initial DnpAB Enzymes and a Two-Component Monooxygenase DnpC1C2

Besides an industrial pollutant, 2,4-dinitrophenol (DNP) has been used illegally as a weight loss drug that had claimed human lives. Little is known about the metabolism of DNP, particularly among Gram-negative bacteria. In this study, two non-contiguous genetic loci of Paraburkholderia (formerly Burkholderia) sp. strain KU-46 genome were identified and four key initial genes (dnpA, dnpB, and dnpC1C2) were characterized to provide molecular and biochemical evidence for the degradation of DNP via the formation of 4-nitrophenol (NP), a pathway that is unique among DNP utilizing bacteria. Reverse transcription PCR analysis indicated that the dnpA gene encoding the initial hydride transferase (28 kDa), and the dnpB gene encoding a nitrite-eliminating enzyme (33 kDa), are inducible by DNP and the two genes are organized in an operon. Purified DnpA and DnpB from overexpression clones in Escherichia coli effected the transformation of DNP to NP via the formation of hydride-Meisenheimer complex of DNP. The function of DnpB appears new since all homologs of DnpB sequences in the protein database are annotated as putative nitrate ABC transporter substrate-binding proteins. The gene cluster responsible for the degradation of DNP after NP formation was designated dnpC1C2DXFER. DnpC1 and DnpC2 were functionally characterized as the respective FAD reductase and oxygenase components of the two-component NP monooxygenase. Both NP and 4-nitrocatechol were shown to be substrates, producing hydroquinone and hydroxyquinol, respectively. Elucidation of the hqdA1A2BCD gene cluster allows the delineation of the final degradation pathway of hydroquinone to {beta}-ketoadipate prior to its entry to the tricarboxylic acid cycle.\n\nImportanceThis study fills a gap in our knowledge and understanding of the genetic basis and biochemical pathway for the degradation of 2,4-dinitrophenol (DNP) in Gram-negative bacteria, represented by the prototypical Paraburkholderia sp. strain KU-46 that metabolizes DNP through the formation of 4-nitrophenol, a pathway unseen by other DNP utilizers. The newly cloned genes could serve as DNA probes in biomonitoring as well as finding application in new biocatalyst development to access green chemicals. By and large, knowledge of the diverse strategies used by microorganisms to degrade DNP will contribute to the development of bioremediation solutions since DNP is an industrial pollutant used widely in the chemical industry for the synthesis of pesticides, insecticides, sulfur dyes, wood preservatives, and explosives, etc. (119 words)

microbiology↗