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Your search keyword '"Masayuki Komada"' showing total 8 results
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8 results on '"Masayuki Komada"'

1. Convergent gene losses and pseudogenizations in multiple lineages of stomachless fishes

Author

Akira Kato, Supriya Pipil, Chihiro Ota, Makoto Kusakabe, Taro Watanabe, Ayumi Nagashima, An-Ping Chen, Zinia Islam, Naoko Hayashi, Marty Kwok-Shing Wong, Masayuki Komada, Michael F. Romero, and Yoshio Takei

Subjects
Biology (General), QH301-705.5
Abstract

Abstract The regressive evolution of independent lineages often results in convergent phenotypes. Several teleost groups display secondary loss of the stomach, and four gastric genes, atp4a, atp4b, pgc, and pga2 have been co-deleted in agastric (stomachless) fish. Analyses of genotypic convergence among agastric fishes showed that four genes, slc26a9, kcne2, cldn18a, and vsig1, were co-deleted or pseudogenized in most agastric fishes of the four major groups. kcne2 and vsig1 were also deleted or pseudogenized in the agastric monotreme echidna and platypus, respectively. In the stomachs of sticklebacks, these genes are expressed in gastric gland cells or surface epithelial cells. An ohnolog of cldn18 was retained in some agastric teleosts but exhibited an increased non-synonymous substitution when compared with gastric species. These results revealed novel convergent gene losses at multiple loci among the four major groups of agastric fish, as well as a single gene loss in the echidna and platypus.

Published
2024
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2. A possible function of Nik-related kinase in the labyrinth layer of delayed delivery mouse placentas

Author

Hiroshi YOMOGITA, Hikaru ITO, Kento HASHIMOTO, Akihiko KUDO, Toshiaki FUKUSHIMA, Tsutomu ENDO, Yoshikazu HIRATE, Yoshihiro AKIMOTO, Masayuki KOMADA, Yoshiakira KANAI, Naoyuki MIYASAKA, and Masami KANAI-AZUMA

Subjects
delayed delivery, nik-related kinase, progesterone, prolactin, trophoblast giant cells, Reproduction, QH471-489, Internal medicine, RC31-1245
Abstract

In mice and humans, Nik-related protein kinase (Nrk) is an X-linked gene that encodes a serine/threonine kinase belonging to GCK group 4. Nrk knockout (Nrk KO) mice exhibit delayed delivery, possibly due to defective communication between the Nrk KO conceptus and its mother. However, the mechanism of delayed labor remains largely unknown. Here, we found that in pregnant mothers with the Nrk KO conceptus, the serum progesterone (P4) and placental lactogen (PL-2) concentrations in late pregnancy were higher than those in the wild type. Moreover, we demonstrated that Nrk is expressed in trophoblast giant cells (TGCs) and syncytiotrophoblast-2 (SynT-2) in the labyrinth layer of the mouse placenta. In the human placenta, NRK is also expressed in Syn-T in villi. Both human Syn-T and mouse TGCs of the labyrinth layer are present within fetal tissues that are in direct contact with the maternal blood. The labyrinth layer of the Nrk KO conceptus was gigantic, with enlarged cytoplasm and Golgi bodies in the TGCs. To investigate the function of Nrk in the labyrinth layer, a differentially expressed gene (DEG) analysis was performed. The DEG analysis revealed that labor-promoting factors, such as prostaglandins, were decreased, and pregnancy-maintaining factors, such as the prolactin family and P4 receptor, were increased. These findings suggest that the Nrk KO mice exhibit delayed delivery owing to high P4 concentrations caused by the hypersecretion of pregnancy-maintaining factors, such as PL-2, from the placenta.

Published
2022
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3. Molecular basis of ubiquitin-specific protease 8 autoinhibition by the WW-like domain

Author

Keijun Kakihara, Kengo Asamizu, Kei Moritsugu, Masahide Kubo, Tetsuya Kitaguchi, Akinori Endo, Akinori Kidera, Mitsunori Ikeguchi, Akira Kato, Masayuki Komada, and Toshiaki Fukushima

Subjects
Biology (General), QH301-705.5
Abstract

In order to advance our understanding of the regulation of Ubiquitin-specific protease 8 (USP8), which is known to play a role in Cushing’s Disease, Kakihara et al identify and characterise amino acids 645–684 of USP8, which serve as an autoinhibitory region. Their pull-down and single-molecule FRET analysis, as well as in silico modelling, suggest that the release of USP8 autoinhibition may underlie Cushing’s disease.

Published
2021
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5. Placental Mammals Acquired Functional Sequences in NRK for Regulating the CK2–PTEN–AKT Pathway and Placental Cell Proliferation

Author

Beni Lestari, Satomi Naito, Akinori Endo, Hidenori Nishihara, Akira Kato, Erika Watanabe, Kimitoshi Denda, Masayuki Komada, and Toshiaki Fukushima

Subjects
Eutheria, urogenital system, Placenta, Intracellular Signaling Peptides and Proteins, PTEN Phosphohydrolase, Protein Serine-Threonine Kinases, equipment and supplies, Mice, Pregnancy, embryonic structures, Genetics, Animals, Female, Phosphorylation, Casein Kinase II, Proto-Oncogene Proteins c-akt, Molecular Biology, hormones, hormone substitutes, and hormone antagonists, Ecology, Evolution, Behavior and Systematics, Cell Proliferation
Abstract

The molecular evolution processes underlying the acquisition of the placenta in eutherian ancestors are not fully understood. Mouse NCK-interacting kinase (NIK)-related kinase (NRK) is expressed highly in the placenta and plays a role in preventing placental hyperplasia. Here, we show the molecular evolution of NRK, which confers its function for inhibiting placental cell proliferation. Comparative genome analysis identified NRK orthologs across vertebrates, which share the kinase and citron homology (CNH) domains. Evolutionary analysis revealed that NRK underwent extensive amino acid substitutions in the ancestor of placental mammals and has been since conserved. Biochemical analysis of mouse NRK revealed that the CNH domain binds to phospholipids, and a region in NRK binds to and inhibits casein kinase-2 (CK2), which we named the CK2-inhibitory region (CIR). Cell culture experiments suggest the following: 1) Mouse NRK is localized at the plasma membrane via the CNH domain, where the CIR inhibits CK2. 2) This mitigates CK2-dependent phosphorylation and inhibition of PTEN and 3) leads to the inhibition of AKT signaling and cell proliferation. Nrk deficiency increased phosphorylation levels of PTEN and AKT in mouse placenta, supporting our hypothesis. Unlike mouse NRK, chicken NRK did not bind to phospholipids and CK2, decrease phosphorylation of AKT, or inhibit cell proliferation. Both the CNH domain and CIR have evolved under purifying selection in placental mammals. Taken together, our study suggests that placental mammals acquired the phospholipid-binding CNH domain and CIR in NRK for regulating the CK2–PTEN–AKT pathway and placental cell proliferation.

Published
2022

6. Molecular basis of ubiquitin-specific protease 8 autoinhibition by the WW-like domain

Author

Kengo Asamizu, Kei Moritsugu, Toshiaki Fukushima, Akinori Kidera, Akinori Endo, Tetsuya Kitaguchi, Masayuki Komada, Akira Kato, Mitsunori Ikeguchi, Masahide Kubo, and Keijun Kakihara

Subjects
Pituitary diseases, QH301-705.5, In silico, medicine.medical_treatment, Medicine (miscellaneous), Article, General Biochemistry, Genetics and Molecular Biology, Deubiquitinating enzyme, Endopeptidases, Ubiquitin specific protease, medicine, Humans, Biology (General), Pituitary ACTH Hypersecretion, chemistry.chemical_classification, Protease, Endosomal Sorting Complexes Required for Transport, biology, Chemistry, Ubiquitination, Enzyme assay, Cell biology, Amino acid, Förster resonance energy transfer, Enzyme mechanisms, Mutation, biology.protein, Activity regulation, Molecular modelling, General Agricultural and Biological Sciences, Ubiquitin Thiolesterase
Abstract

Ubiquitin-specific protease 8 (USP8) is a deubiquitinating enzyme involved in multiple membrane trafficking pathways. The enzyme activity is inhibited by binding to 14-3-3 proteins. Mutations in the 14-3-3-binding motif in USP8 are related to Cushing’s disease. However, the molecular basis of USP8 activity regulation remains unclear. This study identified amino acids 645–684 of USP8 as an autoinhibitory region, which might interact with the catalytic USP domain, as per the results of pull-down and single-molecule FRET assays performed in this study. In silico modelling indicated that the region forms a WW-like domain structure, plugs the catalytic cleft, and narrows the entrance to the ubiquitin-binding pocket. Furthermore, 14-3-3 inhibited USP8 activity partly by enhancing the interaction between the WW-like and USP domains. These findings provide the molecular basis of USP8 autoinhibition via the WW-like domain. Moreover, they suggest that the release of autoinhibition may underlie Cushing’s disease due to USP8 mutations., In order to advance our understanding of the regulation of Ubiquitin-specific protease 8 (USP8), which is known to play a role in Cushing’s Disease, Kakihara et al identify and characterise amino acids 645–684 of USP8, which serve as an autoinhibitory region. Their pull-down and single-molecule FRET analysis, as well as in silico modelling, suggest that the release of USP8 autoinhibition may underlie Cushing’s disease.

Published
2021

7. Placental mammals acquired the functional region and domain in NRK for regulating the CK2-PTEN-AKT pathway and placental cell proliferation

Author

Beni Lestari, Erika Watanabe, Toshiaki Fukushima, Akinori Endo, Akira Kato, Kimitoshi Denda, Masayuki Komada, Satomi Naito, and Hidenori Nishihara

Subjects
biology, urogenital system, Chemistry, Kinase, Cell growth, equipment and supplies, Cell biology, medicine.anatomical_structure, Cell culture, Placenta, embryonic structures, biology.protein, medicine, PTEN, Phosphorylation, Protein kinase B, hormones, hormone substitutes, and hormone antagonists, PI3K/AKT/mTOR pathway
Abstract

The molecular evolution processes underlying the acquisition of the placenta in eutherian ancestors are not fully understood. Mouse NCK-interacting kinase (NIK)-related kinase (NRK) is expressed highly in the placenta and plays a role in preventing placental hyperplasia. Here, we show the molecular evolution of NRK, which confers its function for inhibiting placental cell proliferation. Comparative genome analysis identified NRK orthologues across vertebrates, which share the kinase and citron homology (CNH) domains. Evolutionary analysis revealed that NRK underwent extensive amino acid substitutions in the ancestor of placental mammals and has been since conserved. Biochemical analysis of mouse NRK revealed that the CNH domain binds to phospholipids, and a region in NRK binds to and inhibits casein kinase-2 (CK2), which we named the CK2-inhibitory region (CIR). Cell culture experiments suggest the following: (1) mouse NRK is localised at the plasma membrane via the CNH domain, where the CIR inhibits CK2. (2) This mitigates CK2-dependent phosphorylation and inhibition of PTEN, and (3) leads to the inhibition of AKT signalling and cell proliferation. Nrk deficiency increased phosphorylation levels of PTEN and AKT in mouse placenta, supporting our hypothesis. Unlike mouse NRK, chicken NRK did not bind to phospholipids and CK2, decrease phosphorylation of AKT, or inhibit cell proliferation. Both the CNH domain and CIR have evolved under purifying selection in placental mammals. Taken together, our study suggests that placental mammals acquired the phospholipid-binding CNH domain and CIR in NRK for regulating the CK2-PTEN-AKT pathway and placental cell proliferation.

Published
2021

8. USP8 prevents aberrant NF-κB and Nrf2 activation by counteracting ubiquitin signals from endosomes.

Author

Akinori Endo, Toshiaki Fukushima, Chikage Takahashi, Hikaru Tsuchiya, Fumiaki Ohtake, Sayaka Ono, Tony Ly, Yukiko Yoshida, Keiji Tanaka, Yasushi Saeki, and Masayuki Komada

Subjects
*DEUBIQUITINATING enzymes, *UBIQUITIN, *ENDOSOMES, *UBIQUITINATION, *BLOOD proteins, *MEMBRANE proteins, *ENDOCYTOSIS
Abstract

K63-linked ubiquitin chains attached to plasma membrane proteins serve as tags for endocytosis and endosome-to-lysosome sorting. USP8 is an essential deubiquitinase for the maintenance of endosomal functions. Prolonged depletion of USP8 leads to cell death, but the major effects on cellular signaling pathways are poorly understood. Here, we show that USP8 depletion causes aberrant accumulation of K63-linked ubiquitin chains on endosomes and induces immune and stress responses. Upon USP8 depletion, two different decoders for K63-linked ubiquitin chains, TAB2/3 and p62, were recruited to endosomes and activated the TAK1-NF-κB and Keap1-Nrf2 pathways, respectively. Oxidative stress, an environmental stimulus that potentially suppresses USP8 activity, induced accumulation of K63-linked ubiquitin chains on endosomes, recruitment of TAB2, and expression of the inflammatory cytokine. The results demonstrate that USP8 is a gatekeeper of misdirected ubiquitin signals and inhibits immune and stress response pathways by removing K63-linked ubiquitin chains from endosomes. [ABSTRACT FROM AUTHOR]

Published
2024
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