Publications by authors named "Takehiko Itoh"

In eukaryotes, mRNAs with long poly(A) tails are translationally active, but deadenylation and uridylation of these tails generally cause mRNA degradation. However, the fate of uridylated mRNAs that are not degraded quickly remains obscure. Here, using tail-seq and microinjection of the 3' region of mRNA, we report that some mRNAs in starfish are re-polyadenylated to be translationally active after deadenylation and uridylation.

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Article Synopsis
  • - Community-associated methicillin-resistant Staphylococcus aureus (CA-MRSA) infections are rising as a public health concern, particularly in community settings like maternity clinics, with a specific outbreak in Japan identified through analysis techniques.
  • - A study analyzed 151 CA-MRSA isolates, identifying 133 related to the outbreak, which belonged to a lineage called the TDC clone, part of the clonal complex 30 (SWP clone).
  • - The research highlighted that the TDC clone had been present before the outbreak, showing long persistence in carriers, high transmission within households, and significant genetic changes tied to mobile genetic elements that affected antibiotic resistance.
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Allorecognition-the ability of an organism to discriminate between self and nonself-is crucial to colonial marine animals to avoid invasion by other individuals in the same habitat. The cnidarian hydroid Hydractinia has long been a major research model in studying invertebrate allorecognition, establishing a rich knowledge foundation. In this study, we introduce a new cnidarian model Cladonema radiatum (C.

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Within 15,000 years, the explosive adaptive radiation of haplochromine cichlids in Lake Victoria, East Africa, generated 500 endemic species. In the 1980s, the upsurge of Nile perch, a carnivorous fish artificially introduced to the lake, drove the extinction of more than 200 endemic cichlids. The Nile perch predation particularly harmed piscivorous cichlids, including paedophages, cichlids eat eggs and fries, which is an example of the unique trophic adaptation seen in African cichlids.

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Introduction: X chromosome inactivation (XCI) is an essential mechanism for dosage compensation between females and males in mammals. In females, XCI is controlled by a complex, conserved locus termed the X inactivation center (Xic), in which the lncRNA Xist is the key regulator. However, little is known about the Xic in species with unusual sex chromosomes.

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Green feather algae (Bryopsidales) undergo a unique life cycle in which a single cell repeatedly executes nuclear division without cytokinesis, resulting in the development of a thallus (>100 mm) with characteristic morphology called coenocyte. Bryopsis is a representative coenocytic alga that has exceptionally high regeneration ability: extruded cytoplasm aggregates rapidly in seawater, leading to the formation of protoplasts. However, the genetic basis of the unique cell biology of Bryopsis remains poorly understood.

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Primordial germ cells (PGCs) are pivotal for gonadal development and reproductive success. Though artificial induction of sterility by targeting PGCs are gaining popularity due to its advantages in fish surrogacy and biodiversity management, it is often skill and time intensive. In this study, we have focused on understanding the role of PGCs and the chemotactic SDF-1/CXCR4 signaling on gonad development of Japanese anchovy (JA, Engraulis japonicus), an upcoming marine model organism with eco-commercial values, with an aim to develop a novel, easy, and versatile gonad sterilization method.

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SDF-1/CXCR4 chemokine signaling are indispensable for cell migration, especially the Primordial Germ Cell (PGC) migration towards the gonadal ridge during early development. We earlier found that this signaling is largely conserved in the Japanese anchovy (, EJ), and a mere treatment of CXCR4 antagonist, AMD3100, leads to germ cell depletion and thereafter gonad sterilization. However, the effect of AMD3100 was limited.

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The mutants resistant to a phenylalanine analog, 4-fluorophenylalanine (4FP), were obtained for metabolic engineering of Corynebacterium glutamicum for producing aromatic amino acids synthesized through the shikimate pathway by adaptive laboratory evolution. Culture experiments of the C. glutamicum strains which carry the mutations found in the open reading frame from the 4FP-resistant mutants revealed that the mutations in the open reading frames of aroG (NCgl2098), pheA (NCgl2799) and aroP (NCgl1062) encoding 3-deoxy-d-arabino-heptulosonate-7-phosphate, prephenate dehydratase, and aromatic amino acid transporter are responsible for 4FP resistance and higher concentration of aromatic amino acids in their culture supernatants in the 4FP-resistant strains.

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Article Synopsis
  • This text discusses the first detailed genome assemblies for three endangered species of Tokudaia found in Japan's Ryukyu Islands, showcasing their unique chromosome structures.
  • The genome sequencing utilized advanced methods, resulting in high-quality chromosome-level scaffolds which contain significant amounts of genetic data specific to each species.
  • These findings aim to enhance our understanding of species evolution, particularly in relation to sex determination and chromosomal development in mammals.
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In the Japanese hagfish, Eptatretus burgeri, approximately 21% of the genomic DNA in germ cells (2n = 52) consists of 16 chromosomes (eliminated [E]-chromosomes) that are eliminated from presumptive somatic cells (2n = 36). To uncover the eliminated genome (E-genome), we have identified 16 eliminated repetitive DNA families from eight hagfish species, with 11 of these repeats being selectively amplified in the germline genome of E. burgeri.

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The genomes of obligate bacterial co-symbionts of the green rice leafhopper , which is notorious as an agricultural pest, were determined. The streamlined genomes of " Sulcia muelleri" and " Nasuia deltocephalinicola" exhibited complementary metabolic pathways for synthesizing essential nutrients that contribute to host adaptation.

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Cephonodes hylas, the coffee bee hawk moth is a hawk moth species with unique characteristics, such as larvae feeding on gardenia, overcoming the toxicity of its iridoid glycosides, diurnal adults, and transparent wings. Although C. hylas is a fascinating model for molecular biological research, genome sequence analysis-based genetic approaches to elucidate these peculiarities have not yet been undertaken.

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The prediction of gene structure within the genome sequence is the starting point of genome analysis, and its accuracy has a significant impact on the quality of subsequent analyses. Gene structure prediction is roughly divided into RNA-Seq-based methods, ab initio-based methods, homology-based methods, and the integration of individual prediction methods. Integrated methods are mainstream in recent genome projects because they improve prediction accuracy by combining or taking the best individual prediction findings; however, adequate prediction accuracy for eukaryotic species has not yet been achieved.

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Chromosome-level haplotype-resolved genome assembly is an important resource in molecular biology. However, current de novo haplotype assemblers require parental data or reference genomes and often fail to provide chromosome-level results. We present GreenHill, a novel scaffolding and phasing tool that considers various assemblers' contigs as input to reconstruct chromosome-level haplotypes using Hi-C without parental or reference data.

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In Japan, wasabi (Eutrema japonicum) is an important traditional condiment, and is recognized as an endemic species. In the present study, we generated a chromosome-level and haplotype-resolved reference genome for E. japonicum using PacBio CLR (continuous long reads), Illumina, and Hi-C sequencing data.

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The modification of photosynthesis-related genes in plastid genomes may improve crop yields. Recently, we reported that a plastid-targeting base editor named ptpTALECD, in which a cytidine deaminase DddA functions as the catalytic domain, can homoplasmically substitute a targeted C to T in plastid genomes of Arabidopsis thaliana. However, some target Cs were not substituted.

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Article Synopsis
  • * The study involved genome sequencing of 510 strains, including 147 from Japan, and analyzed variations in Stx2 production levels, which are associated with disease severity.
  • * Results showed distinct genetic diversity in Stx2a phages among the lineages, particularly that SG8_30 strains produced more Stx2 and caused more severe illnesses compared to SG8_32 strains.
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Polyhydroxyalkanoate (PHA) is a type of biopolymer produced by most bacteria and archaea, resembling thermoplastic with biodegradability and biocompatibility features. Here, we report the complete genome of a PHA producer, Aquitalea sp. USM4, isolated from Perak, Malaysia.

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Mammalian sex chromosomes are highly conserved, and sex is determined by on the Y chromosome. Two exceptional rodent groups in which some species lack a Y chromosome and offer insights into how novel sex genes can arise and replace , leading to sex chromosome turnover. However, intensive study over three decades has failed to reveal the identity of novel sex genes in either of these lineages.

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The paper nautilus or greater argonaut, Argonauta argo, is a species of octopods which is characterized by its pelagic lifestyle and by the presence of a protective spiral-shaped shell-like eggcase in females. To reveal the genomic background of how the species adapted to the pelagic lifestyle and acquired its shell-like eggcase, we sequenced the draft genome of the species. The genome size was 1.

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Alternative splicing underpins functional diversity in proteins and the complexity and diversity of eukaryotes. An example is the doublesex gene, the key transcriptional factor in arthropod sexual differentiation. doublesex is controlled by sex-specific splicing and promotes both male and female differentiation in holometabolan insects, whereas in hemimetabolan species, doublesex has sex-specific isoforms but is not required for female differentiation.

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It has long been suggested that dimorphic female-limited Batesian mimicry of two closely related butterflies, and is controlled by supergenes. Whole-genome sequencing, genome-wide association studies and functional analyses have recently identified mimicry supergenes, including the gene. Although supergenes of both the species are composed of highly divergent regions between mimetic and non-mimetic alleles and are located at the same chromosomal locus, they show critical differences in genomic architecture, particularly with or without an inversion: .

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Asobara japonica is an endoparasitic wasp that parasitizes Drosophila flies. It synthesizes various toxic components in the venom gland and injects them into host larvae during oviposition. To identify and characterize these toxic components for enabling parasitism, we performed the whole-genome sequencing (WGS) and devised a protocol for RNA interference (RNAi) with A.

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Beyond their well-known role in respiration, mitochondria of land plants contain biologically essential and/or agriculturally important genes whose function and regulation are not fully understood. Until recently, it has been difficult to analyze these genes or, in the case of crops, to improve their functions, due to a lack of methods for stably modifying plant mitochondrial genomes. In rice, rapeseed, and Arabidopsis thaliana, mitochondria-targeting transcription activator-like effector nucleases (mitoTALENs) have recently been used to disrupt targeted genes in an inheritable and stable manner.

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