Publications by authors named "Katsushi Yamaguchi"

Sex chromosomes are expected to coevolve with their respective sex, potentially disfavoring their co-occurrence as cosexuality evolves. This effect is expected to be stronger where sex chromosomes are restricted to one sex, such as in plants expressing sex in their haploid stage. We assess this hypothesis in liverworts with U/V sex chromosomes, ancestral dioicy, and several independent transitions to monoicy (cosexuality).

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Introduction: The ANGUSTIFOLIA3 (AN3) gene encodes a transcriptional co-activator for cell proliferation in Arabidopsis thaliana leaves. We previously showed that Physcomitrium patens AN3 orthologs promote gametophore shoot formation through arginine metabolism.

Objectives: We analyzed the role of AN3 in Arabidopsis thaliana to understand how seedling growth is regulated by metabolic and physiological modulations.

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Polyrhachis lamellidens is a temporary socially parasitic ant. The newly mated P. lamellidens queen takes over a colony of several Camponotus ant species and uses the labour of the host workers in the early stages of social parasitism.

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Plants accumulate starch and triacylglycerols (TAGs) as carbon sources. Leaves primarily store starch in chloroplasts, with some TAGs stored in lipid droplets, but how carbon resource allocation is regulated in leaves during cellular metabolism is largely unknown. Using a forward genetics approach, we isolated an Arabidopsis thaliana mutant with more lipid droplets in its leaves than the wild type, named lipid rich 1 (liri1).

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Trilocha varians is a member of the bombycid moths. Since T. varians has a considerably shorter generation period than the prevailing model species, Bombyx mori, this species would be a novel model insect in Lepidoptera.

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The wild silk moth, Bombyx mandarina, is the closest relative of the domesticated silk moth, Bombyx mori. National BioResource Project of Japan (NBRP) maintains a B. mandarina strain derived from individuals captured at Sakado (Saitama, Japan) in 1982.

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Populations in extreme environments at the margins of a species' range are often the most vulnerable to climate change, but they may also experience novel evolutionary processes, such as secondary contact and hybridization with their relatives. The range overlap resulting from secondary contact with related species that have adapted to different climatic zones may act as corridors for adaptive introgression. To test this hypothesis, we examined the hybrid zones along the altitude of two closely related species, one temperate and the other subtropical species, at their southern and northern limits on Yakushima Island, Japan.

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Background: The Japanese cedar (Cryptomeria japonica D. Don) is one of the most important Japanese forest trees, occupying approximately 44% of artificial forests and planted in East Asia, the Azores Archipelago, and certain islands in the Indian Ocean. Although the huge genome of the species (ca.

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Membrane proteins targeted to the plasma membrane are first transported from the endoplasmic reticulum (ER) to the Golgi apparatus. This study explored the mechanisms controlling plasma membrane trafficking of the boric acid channel AtNIP5;1 from the ER. Imaging-based screening using transgenic Arabidopsis identified six mutants in which GFP-NIP5;1 was localized in the ER in addition to the plasma membrane.

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Orchids and arbuscular mycorrhiza (AM) plants evolved independently and have different structures and fungal partners, but they both facilitate nutrient uptake. Orchid mycorrhiza (OM) supports orchid seed germination, but unlike AM, its role in disease resistance of mature plants is largely unknown. Here, we examined whether OM induces systemic disease resistance against a necrotrophic pathogen in a similar fashion to AM.

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Fem is a W-linked gene that encodes a piRNA precursor, and its product, Fem piRNA, is a master factor of female determination in Bombyx mori. Fem has low similarity to any known sequences, and the origin of Fem remains unclear. So far, two hypotheses have been proposed for the origin of Fem: The first hypothesis is that Fem is an allele of Masc, which assumes that the W chromosome was originally a homologous chromosome of the Z chromosome.

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Understanding the genetic basis for adapting to thermal environments is important due to serious effects of global warming on ectothermic species. Various genes associated with thermal adaptation in lizards have been identified mainly focusing on changes in gene expression or the detection of positively selected genes using coding regions. Only a few comprehensive genome-wide analyses have included noncoding regions.

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For understanding the evolutionary mechanism of sexually selected exaggerated traits, it is essential to uncover its molecular basis. By using broad-horned flour beetle that has male-specific exaggerated structures (mandibular horn, head horn and gena enlargement), we investigated the transcriptomic and functional characters of sex-biased genes. Comparative transcriptome of male vs.

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Orchids parasitically depend on external nutrients from mycorrhizal fungi for seed germination. Previous findings suggest that orchids utilize a genetic system of mutualistic arbuscular mycorrhizal (AM) symbiosis, in which the plant hormone gibberellin (GA) negatively affects fungal colonization and development, to establish parasitic symbiosis. Although GA generally promotes seed germination in photosynthetic plants, previous studies have reported low sensitivity of GA in seed germination of mycoheterotrophic orchids where mycorrhizal symbiosis occurs concurrently.

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The mode of sex determination in vertebrates can be categorized as genotypic or environmental. In the case of genotypic sex determination (GSD), the sexual fate of an organism is determined by the chromosome composition with some having dominant genes, named sex-determining genes, that drive the sex phenotypes. By contrast, many reptiles exhibit environmental sex determination (ESD), whereby environmental stimuli drive sex determination, and most notably temperature.

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Host plant-derived strigolactones trigger hyphal branching in arbuscular mycorrhizal (AM) fungi, initiating a symbiotic interaction between land plants and AM fungi. However, our previous studies revealed that gibberellin-treated lisianthus (Eustoma grandiflorum, Gentianaceae) activates rhizospheric hyphal branching in AM fungi using unidentified molecules other than strigolactones. In this study, we analyzed independent transcriptomic data of E.

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Pollinosis, also known as pollen allergy or hay fever, is a global problem caused by pollen produced by various plant species. The wind-pollinated Japanese cedar () is the largest contributor to severe pollinosis in Japan, where increasing proportions of people have been affected in recent decades. The () locus of Japanese cedar controls pollen production, and its homozygous mutants () show abnormal pollen development after the tetrad stage and produce no mature pollen.

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Aims: Schizophrenia is a chronic relapsing psychiatric disorder that is characterized by many symptoms and has a high heritability. There were studies showing that the phospholipid abnormalities in subjects with schizophrenia (Front Biosci, S3, 2011, 153; Schizophr Bull, 48, 2022, 1125; Sci Rep, 7, 2017, 6; Anal Bioanal Chem, 400, 2011, 1933). Disturbances in prefrontal cortex phospholipid and fatty acid composition have been reported in subjects with schizophrenia (Sci Rep, 7, 2017, 6; Anal Bioanal Chem, 400, 2011, 1933; Schizophr Res, 215, 2020, 493; J Psychiatr Res, 47, 2013, 636; Int J Mol Sci, 22, 2021).

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The Japanese rhinoceros beetle Trypoxylus dichotomus is a giant beetle with distinctive exaggerated horns present on the head and prothoracic regions of the male. T. dichotomus has been used as a research model in various fields such as evolutionary developmental biology, ecology, ethology, biomimetics, and drug discovery.

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Excess boron (B) is toxic to plants and thereby causes DNA damage and cell death in root meristems. However, the underlying mechanisms which link boron and DNA damage remain unclear. It has been reported that the mutant of the 26S proteasome is sensitive to excess boron, resulting in more frequent cell death in root meristem and reduced root elongation.

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An Arabidopsis mutant displaying impaired stomatal responses to CO , cdi4, was isolated by a leaf thermal imaging screening. The mutated gene PECT1 encodes CTP:phosphorylethanolamine cytidylyltransferase. The cdi4 exhibited a decrease in phosphatidylethanolamine levels and a defect in light-induced stomatal opening as well as low-CO -induced stomatal opening.

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Article Synopsis
  • Calcium deficiency negatively impacts agricultural yield and quality, with varying susceptibility among different crops and cultivars.
  • A novel gene related to low calcium tolerance was identified, revealing that a specific mutant strain of plants is sensitive to low calcium levels, which was linked to the gene's function.
  • Research showed that the shoot growth of the calcium-sensitive mutants was hindered compared to wild-type plants, and the interaction between the identified gene and previously known genes suggests a combined impact on low calcium tolerance.
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Background: Detecting genomic variants and their accumulation processes during species diversification and adaptive radiation is important for understanding the molecular and genetic basis of evolution. Anolis lizards in the West Indies are good models for studying evolutionary mechanisms because of the repeated evolution of their morphology and the ecology. We performed de novo genome assembly of six Cuban Anolis lizards with different ecomorphs and thermal habitats (Anolis isolepis, Anolis allisoni, Anolis porcatus, Anolis allogus, Anolis homolechis, and Anolis sagrei).

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Crops that exhibit symptoms of calcium (Ca) deficiency constitute a major agricultural problem. Molecular breeding of resistant cultivars is a promising method for overcoming this problem. However, the involved genes must first be identified.

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Non-biting midges (Chironomidae) are known to inhabit a wide range of environments, and certain species can tolerate extreme conditions, where the rest of insects cannot survive. In particular, the sleeping chironomid is known for the remarkable ability of its larvae to withstand almost complete desiccation by entering a state called anhydrobiosis. Chromosome numbers in chironomids are higher than in other dipterans and this extra genomic resource might facilitate rapid adaptation to novel environments.

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