11 results on '"Yasuhiro Kamei"'
Search Results
2. The pentameric hydrocoel lobes organize adult pentameral structures in a sea cucumber, Apostichopus japonicus
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Sumio Udagawa, Akiko Nagai, Mani Kikuchi, Akihito Omori, Atsushi Tajika, Mieko Saito, Toru Miura, Naoki Irie, Yasuhiro Kamei, and Mariko Kondo
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Stichopus ,Sea Cucumbers ,Metamorphosis, Biological ,Animals ,Water ,Cell Biology ,Molecular Biology ,Echinodermata ,Developmental Biology - Abstract
Despite being one of the bilaterians, the body plan of echinoderms shifts from bilateral symmetry to five-fold radial, or pentaradial symmetry during embryogenesis or their metamorphosis. While the clarification of the developmental mechanism behind this transition will be a basis for understanding their unique body plan evolution, it is still poorly understood. With this regard, the hydrocoel, a mesodermal coelom formed on the left side of bilateral larva, would be a clue for understanding the mechanism as it is the first pentaradial structure that appears before metamorphosis and develops into the water vascular system of adults. By analyzing the development of a sea cucumber, Apostichopus japonicus, we found that the hydrocoel expresses genes related in muscle and neural formation such as myosin heavy chain, tropomyosin, soxC, and elav, implying that cells of the hydrocoel contributes to muscle and neural structures in the adult. Furthermore, ablation of one of the hydrocoel lobes led to incomplete development of adult pentameral structures. The ablation of primary hydrocoel lobes resulted in the reduction in tentacles and the ablation of secondary hydrocoel lobes resulted in the reduction in water vascular canals and nerve cords. Our findings suggest that the hydrocoel lobes may serve as a potential organizing center for establishing the pentaradial body plan in echinoderms.
- Published
- 2022
3. Development of a screening system for agents that modulate taste receptor expression with the CRISPR-Cas9 system in medaka
- Author
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Kana Beppu, Rie Tsutsumi, Satoshi Ansai, Nana Ochiai, Mai Terakawa, Marie Mori, Masashi Kuroda, Kazuki Horikawa, Takumi Tomoi, Joe Sakamoto, Yasuhiro Kamei, Kiyoshi Naruse, and Hiroshi Sakaue
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Taste ,Green Fluorescent Proteins ,Oryzias ,Quality of Life ,Biophysics ,Animals ,Gene Expression ,Cell Biology ,CRISPR-Cas Systems ,Dysgeusia ,Molecular Biology ,Biochemistry - Abstract
Taste recognition mediated by taste receptors is critical for the survival of animals in nature and is an important determinant of nutritional status and quality of life in humans. However, many factors including aging, diabetes, zinc deficiency, infection with influenza or cold viruses, and chemotherapy can trigger dysgeusia, for which a standard treatment has not been established. We here established an engineered strain of medaka (Oryzias latipes) that expresses green fluorescent protein (GFP) from the endogenous taste 1 receptor 3 (T1R3) gene locus with the use of the CRISPR-Cas9 system. This T1R3-GFP knock-in (KI) strain allows direct visualization of expression from this locus by monitoring of GFP fluorescence. The pattern of GFP expression in the T1R3-GFP KI fish thus mimicked that of endogenous T1R3 gene expression. Furthermore, exposure of T1R3-GFP KI medaka to water containing monosodium glutamate or the anticancer agent 5-fluorouracil resulted in an increase or decrease, respectively, in GFP fluorescence intensity, effects that also recapitulated those on T1R3 mRNA abundance. Finally, screening for agents that affect GFP fluorescence intensity in T1R3-GFP KI medaka identified tryptophan as an amino acid that increases T1R3 gene expression. The establishment of this screening system for taste receptor expression in medaka provides a new tool for the development of potential therapeutic agents for dysgeusia.
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- 2022
4. Ovarian aromatase loss-of-function mutant medaka undergo ovary degeneration and partial female-to-male sex reversal after puberty
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Yoshitaka Nagahama, Kaoru Ohno, Masatoshi Nakamoto, Penny Swanson, Yoshihito Taniguchi, Yasuhiro Kamei, Takashi Sakamoto, Kiyoshi Naruse, Graham Young, Takeshi Todo, Yasushi Shibata, and Takeshi Usami
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Male ,0301 basic medicine ,endocrine system ,medicine.medical_specialty ,food.ingredient ,endocrine system diseases ,Somatic cell ,Oryzias ,Down-Regulation ,Ovary ,Biology ,Biochemistry ,Germline ,Vitellogenins ,03 medical and health sciences ,Aromatase ,0302 clinical medicine ,Endocrinology ,food ,Ovarian Follicle ,Loss of Function Mutation ,Yolk ,Internal medicine ,Testis ,medicine ,Animals ,Cell Lineage ,Amino Acid Sequence ,Sexual Maturation ,Molecular Biology ,Base Sequence ,Gene Expression Profiling ,Estrogens ,Sex Determination Processes ,Sex reversal ,biology.organism_classification ,Up-Regulation ,030104 developmental biology ,medicine.anatomical_structure ,biology.protein ,Female ,Stem cell ,030217 neurology & neurosurgery - Abstract
Although estrogens have been generally considered to play a critical role in ovarian differentiation in non-mammalian vertebrates, the specific functions of estrogens during ovarian differentiation remain unclear. We isolated two mutants with premature stops in the ovarian aromatase (cyp19a1) gene from an N-ethyl-N-nitrosourea-based gene-driven mutagenesis library of the medaka, Oryzias latipes. In XX mutants, gonads first differentiated into normal ovaries containing many ovarian follicles that failed to accumulate yolk. Subsequently, ovarian tissues underwent extensive degeneration, followed by the appearance of testicular tissues on the dorsal side of ovaries. In the newly formed testicular tissue, strong expression of gsdf was detected in sox9a2-positive somatic cells surrounding germline stem cells suggesting that gsdf plays an important role in testicular differentiation during estrogen-depleted female-to-male sex reversal. We conclude that endogenous estrogens synthesized after fertilization are not essential for early ovarian differentiation but are critical for the maintenance of adult ovaries.
- Published
- 2018
5. Estrogen receptor 2b is the major determinant of sex-typical mating behavior and sexual preference in medaka
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Daichi Miyazoe, Tomoko Ishikawa-Fujiwara, Yasuhiro Kamei, Takeshi Usami, Yoshitaka Nagahama, Rie Togawa, Yukiko Kikuchi, Masayoshi Miyata, Kaoru Ohno, Kiyoshi Nakasone, Takeshi Todo, Yuji Nishiike, Keiko Yokoyama, and Kataaki Okubo
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Male ,0301 basic medicine ,medicine.medical_specialty ,medicine.drug_class ,Feminization (biology) ,Oryzias ,Biology ,General Biochemistry, Genetics and Molecular Biology ,Sexual Behavior, Animal ,03 medical and health sciences ,0302 clinical medicine ,Internal medicine ,medicine ,Animals ,Mating ,Gonadal Steroid Hormones ,reproductive and urinary physiology ,Estradiol ,Reproduction ,Sex reversal ,Androgen ,Sexual dimorphism ,Androgen receptor ,030104 developmental biology ,Endocrinology ,Receptors, Estrogen ,Estrogen ,Sex steroid ,Female ,General Agricultural and Biological Sciences ,030217 neurology & neurosurgery - Abstract
Male and female animals typically display innate sex-specific mating behaviors, which, in vertebrates, are highly dependent on sex steroid signaling. While estradiol-17β (E2) signaling through estrogen receptor 2 (ESR2) serves to defeminize male mating behavior in rodents, the available evidence suggests that E2 signaling is not required in teleosts for either male or female mating behavior. Here, we report that female medaka deficient for Esr2b, a teleost ortholog of ESR2, are not receptive to males but rather court females, despite retaining normal ovarian function with an unaltered sex steroid milieu. Thus, contrary to both prevailing views in rodents and teleosts, E2/Esr2b signaling in the brain plays a decisive role in feminization and demasculinization of female mating behavior and sexual preference in medaka. Further behavioral testing showed that mutual antagonism between E2/Esr2b signaling and androgen receptor-mediated androgen signaling in adulthood induces and actively maintains sex-typical mating behaviors and preference. Our results also revealed that the female-biased sexual dimorphism in esr2b expression in the telencephalic and preoptic nuclei implicated in mating behavior can be reversed between males and females by altering the sex steroid milieu in adulthood, likely via mechanisms involving direct E2-induced transcriptional activation. In addition, Npba, a neuropeptide mediating female sexual receptivity, was found to act downstream of E2/Esr2b signaling in these brain nuclei. Collectively, these functional and regulatory mechanisms of E2/Esr2b signaling presumably underpin the neural mechanism for induction, maintenance, and reversal of sex-typical mating behaviors and sexual preference in teleosts, at least in medaka.
- Published
- 2021
6. Characterization of assortative mating in medaka: Mate discrimination cues and factors that bias sexual preference
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Shoji Fukamachi, Shoichi Higashi, Yasuhiro Kamei, and Umi Utagawa
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Male ,0301 basic medicine ,Brightness ,Light ,genetic structures ,Oryzias ,Color ,Biology ,Choice Behavior ,Sexual Behavior, Animal ,03 medical and health sciences ,Behavioral Neuroscience ,Endocrinology ,Animals ,Mating ,Sensory cue ,Hue ,Communication ,Endocrine and Autonomic Systems ,business.industry ,Reproduction ,Assortative mating ,Mating Preference, Animal ,030104 developmental biology ,Odor ,Mate choice ,Evolutionary biology ,Female ,Monochromatic color ,Cues ,business - Abstract
Somatolactin alpha (SLα) is a peptide hormone that regulates skin color, and SLα-deficient and SLα-excess strains have been established in medaka (Oryzias latipes). Their skin colors differ conspicuously and males prefer to mate with females from the same strain. Pre-mating sexual isolation in this model vertebrate provides an ideal platform for investigating the molecular mechanisms of mate choice. Thus, we studied the sensory cues utilized by these fish to discriminate the same and different strains. When males were given a choice under monochromatic light, where the skin colors differed only in terms of brightness but not in hue, mating occurred but it was not assortative. This suggests that: (1) a visual cue is essential for mate discrimination rather than odor or acoustic cues; (2) the visual cue is color and not shape, size, or motion; and (3) the color cue needs to be perceived as the relative balance of brightness at multiple wavelengths rather than the brightness at a specific wavelength. In addition, we introduced another skin-color mutation into the SLα-excess strain and found that this new strain and the original SLα-excess strain, which also overexpressed SLα but exhibited distinct skin colors, preferred different colors. This demonstrates that SLα is not a primary determinant of sexual preference. The symmetrically biased sexual preferences of the SLα-deficient and SLα-excess strains may be acquired postnatally depending on their individual skin color or that of tank mates.
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- 2016
7. Transcriptional regulators in the Hippo signaling pathway control organ growth in Xenopus tadpole tail regeneration
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Haruki Ochi, Hitoshi Yokoyama, Koji Tamura, Hajime Ogino, Aiko Kawasumi, Yasuhiro Kamei, and Shinichi Hayashi
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Tail ,Hot Temperature ,Transcription, Genetic ,Hippo pathway ,Xenopus ,Green Fluorescent Proteins ,Yap1 ,Protein Serine-Threonine Kinases ,Xenopus Proteins ,Animals, Genetically Modified ,Xenopus laevis ,Animals ,Regeneration ,TEAD4 ,Molecular Biology ,Mitosis ,Neurons ,YAP1 ,Hippo signaling pathway ,Tail regeneration ,biology ,Cell growth ,Stem Cells ,Regeneration (biology) ,Gene Expression Regulation, Developmental ,YAP-Signaling Proteins ,Tead4 ,Cell Biology ,Anatomy ,biology.organism_classification ,Cell biology ,DNA-Binding Proteins ,Size control ,Spinal Cord ,Hippo signaling ,Trans-Activators ,Signal Transduction ,Developmental Biology - Abstract
The size and shape of tissues are tightly controlled by synchronized processes among cells and tissues to produce an integrated organ. The Hippo signaling pathway controls both cell proliferation and apoptosis by dual signal-transduction states regulated through a repressive kinase cascade. Yap1 and Tead, transcriptional regulators that act downstream of the Hippo signaling kinase cascade, have essential roles in regulating cell proliferation. In amphibian limb or tail regeneration, the local tissue outgrowth terminates when the correct size is reached, suggesting that organ size is strictly controlled during epimorphic organ-level regeneration. We recently demonstrated that Yap1 is required for the regeneration of Xenopus tadpole limb buds (Hayashi et al., 2014, Dev. Biol. 388, 57–67), but the molecular link between the Hippo pathway and organ size control in vertebrate epimorphic regeneration is not fully understood. To examine the requirement of Hippo pathway transcriptional regulators in epimorphic regeneration, including organ size control, we inhibited these regulators during Xenopus tadpole tail regeneration by overexpressing a dominant-negative form of Yap (dnYap) or Tead4 (dnTead4) under a heat-shock promoter in transgenic animal lines. Each inhibition resulted in regeneration defects accompanied by reduced cell mitosis and increased apoptosis. Single-cell gene manipulation experiments indicated that Tead4 cell-autonomously regulates the survival of neural progenitor cells in the regenerating tail. In amphibians, amputation at the proximal level of the tail (deep amputation) results in faster regeneration than that at the distal level (shallow amputation), to restore the original-sized tail with similar timing. However, dnTead4 overexpression abolished the position-dependent differential growth rate of tail regeneration. These results suggest that the transcriptional regulators in the Hippo pathway, Tead4 and Yap1, are required for general vertebrate epimorphic regeneration as well as for organ size control in appendage regeneration. In regenerative medicine, these findings should contribute to the development of three-dimensional organs with the correct size for a patient’s body.
- Published
- 2014
8. Action Spectrum Analysis of UVR Genotoxicity for Skin: The Border Wavelengths between UVA and UVB Can Bring Serious Mutation Loads to Skin
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Tetsuya Ono, Hironobu Ikehata, Kazuo Yamamoto, Yasukazu Daigaku, Nobuo Munakata, Shingo Nakamura, Shoichi Higashi, Masakatsu Watanabe, Yasuhiro Kamei, Yoshiya Furusawa, and Kotaro Hieda
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Erythema ,Ultraviolet Rays ,DNA damage ,Mutant ,Apoptosis ,Mice, Transgenic ,Human skin ,Dermatology ,Biology ,medicine.disease_cause ,Biochemistry ,Mice ,Risk Factors ,medicine ,Animals ,Molecular Biology ,Skin ,Action spectrum ,integumentary system ,Spectrum Analysis ,fungi ,Dose-Response Relationship, Radiation ,Cell Biology ,Disease Models, Animal ,Dose–response relationship ,Lac Operon ,Mutation ,Cancer research ,medicine.symptom ,Genotoxicity ,DNA Damage - Abstract
UVR causes erythema, which has been used as a standardized index to evaluate the risk of UVR for human skin. However, the genotoxic significance of erythema has not been elucidated clearly. Here, we characterized the wavelength dependence of the genotoxic and erythematic effects of UVR for the skin by analyzing the induction kinetics of mutation and inflammation in mouse skin using lacZ-transgenic mice and monochromatic UVR sources. We determined their action spectra and found a close correlation between erythema and an epidermisspecific antigenotoxic response, mutation induction suppression (MIS), which suppressed the mutant frequencies (MFs) to a constant plateau level only 2–3-fold higher than the background MF at the cost of apoptotic cell death, suggesting that erythema may represent the threshold beyond which the antigenotoxic but tissuedestructive MIS response commences. However, we unexpectedly found that MIS attenuates remarkably at the border wavelengths between UVA and UVB around 315 nm, elevating the MF plateaus up to levels B40-fold higher than the background level. Thus, these border wavelengths can bring heavier mutation loads to the skin than the otherwise more mutagenic and erythematic shorter wavelengths, suggesting that erythema-based UVR risk evaluation should be reconsidered.
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- 2013
- Full Text
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9. DNA Damage-induced Ubiquitylation of RFC2 Subunit of Replication Factor C Complex
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Takeshi Todo, Hidekazu Hiroaki, Kenji Kamiya, Cyrus Vaziri, Tomoko Ishikawa, Yasuhiro Kamei, Haruo Ohmori, Yuji Masuda, Toshiki Tsurimoto, Satoshi Tateishi, Junya Tomida, Tadahiro Shiomi, Ihnyoung Song, and Jin-Hyeong Kim
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DNA Replication ,Alkylating Agents ,DNA Repair ,DNA repair ,Ubiquitin-Protein Ligases ,Mutation, Missense ,Eukaryotic DNA replication ,Biology ,Biochemistry ,DNA polymerase delta ,Cell Line ,Ligases ,DNA replication factor CDT1 ,Replication factor C ,Proliferating Cell Nuclear Antigen ,Humans ,Phosphorylation ,Replication Protein C ,Molecular Biology ,Replication protein A ,DNA clamp ,Ubiquitination ,DNA replication ,Hydrogen Peroxide ,Cell Biology ,Oxidants ,Molecular biology ,Cell biology ,DNA-Binding Proteins ,Amino Acid Substitution ,Multiprotein Complexes ,Ubiquitin-Conjugating Enzymes ,DNA: Replication, Repair, Recombination, and Chromosome Dynamics ,biology.protein ,Protein Processing, Post-Translational ,DNA Damage - Abstract
Many proteins involved in DNA replication and repair undergo post-translational modifications such as phosphorylation and ubiquitylation. Proliferating cell nuclear antigen (PCNA; a homotrimeric protein that encircles double-stranded DNA to function as a sliding clamp for DNA polymerases) is monoubiquitylated by the RAD6-RAD18 complex and further polyubiquitylated by the RAD5-MMS2-UBC13 complex in response to various DNA-damaging agents. PCNA mono- and polyubiquitylation activate an error-prone translesion synthesis pathway and an error-free pathway of damage avoidance, respectively. Here we show that replication factor C (RFC; a heteropentameric protein complex that loads PCNA onto DNA) was also ubiquitylated in a RAD18-dependent manner in cells treated with alkylating agents or H2O2. A mutant form of RFC2 with a D228A substitution (corresponding to a yeast Rfc4 mutation that reduces an interaction with replication protein A (RPA), a single-stranded DNA-binding protein) was heavily ubiquitylated in cells even in the absence of DNA damage. Furthermore RFC2 was ubiquitylated by the RAD6-RAD18 complex in vitro, and its modification was inhibited in the presence of RPA. The inhibitory effect of RPA on RFC2 ubiquitylation was relatively specific because RAD6-RAD18-mediated ubiquitylation of PCNA was RPA-insensitive. Our findings suggest that RPA plays a regulatory role in DNA damage responses via repression of RFC2 ubiquitylation in human cells.
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- 2008
10. Quantitative and comparative analysis of tissue deformation dynamics for chick and Xenopus limb morphogenesis
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Yasuhiro Kamei, Koji Tamura, Hitoshi Yokoyama, Yoshihiro Morishita, Takayuki Suzuki, and Aiko Kawasumi
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Embryology ,Tissue deformation ,Dynamics (mechanics) ,Xenopus ,Anatomy ,Biology ,biology.organism_classification ,Limb morphogenesis ,Developmental Biology ,Cell biology - Published
- 2017
11. Opsin 5 as a deep brain photoreceptor regulating photoperiodism
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Shosei Yoshida, Takashi Yoshimura, Kanjun Hirunagi, Shizufumi Ebihara, Keisuke Ikegami, Yasuhiro Kamei, Shoichi Higashi, Hiroko Ono, Naoyuki Yamamoto, Yusuke Nakane, and Yoshihiro Kubo
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photoperiodism ,Opsin ,General Neuroscience ,General Medicine ,Biology ,Cell biology - Published
- 2011
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