CVClient

Tsunehiro Mizushima

  (水島 恒裕)

Profile Information

Affiliation
Professor, University of Hyogo
Degree
博士(理学)(大阪大学)

Researcher number
90362269
J-GLOBAL ID
200901074435540475
researchmap Member ID
1000366778

External link

Papers

 68
  • Tadashi Satoh, Maho Yagi-Utsumi, Nozomi Ishii, Tsunehiro Mizushima, Hirokazu Yagi, Ryuichi Kato, Yuriko Tachida, Hiroaki Tateno, Ichiro Matsuo, Koichi Kato, Tadashi Suzuki, Yukiko Yoshida
    FEBS letters, Aug 22, 2024  
    The cytosolic peptide:N-glycanase (PNGase) is involved in the quality control of N-glycoproteins via the endoplasmic reticulum-associated degradation (ERAD) pathway. Mutations in the gene encoding cytosolic PNGase (NGLY1 in humans) cause NGLY1 deficiency. Recent findings indicate that the F-box protein FBS2 of the SCFFBS2 ubiquitin ligase complex can be a promising drug target for NGLY1 deficiency. Here, we determined the crystal structure of bovine FBS2 complexed with the adaptor protein SKP1 and a sugar ligand, Man3GlcNAc2, which corresponds to the core pentasaccharide of N-glycan. Our crystallographic data together with NMR data revealed the structural basis of disparate sugar-binding specificities in homologous FBS proteins and identified a potential druggable pocket for in silico docking studies. Our results provide a potential basis for the development of selective inhibitors against FBS2 in NGLY1 deficiency.
  • Kazuya Nishio, Tomoyuki Kawarasaki, Yuki Sugiura, Shunsuke Matsumoto, Ayano Konoshima, Yuki Takano, Mayuko Hayashi, Fumihiko Okumura, Takumi Kamura, Tsunehiro Mizushima, Kunio Nakatsukasa
    Science advances, 9(15) eadf1956, Apr 14, 2023  Peer-reviewed
    Deficiencies in mitochondrial protein import are associated with a number of diseases. However, although nonimported mitochondrial proteins are at great risk of aggregation, it remains largely unclear how their accumulation causes cell dysfunction. Here, we show that nonimported citrate synthase is targeted for proteasomal degradation by the ubiquitin ligase SCFUcc1. Unexpectedly, our structural and genetic analyses revealed that nonimported citrate synthase appears to form an enzymatically active conformation in the cytosol. Its excess accumulation caused ectopic citrate synthesis, which, in turn, led to an imbalance in carbon flux of sugar, a reduction of the pool of amino acids and nucleotides, and a growth defect. Under these conditions, translation repression is induced and acts as a protective mechanism that mitigates the growth defect. We propose that the consequence of mitochondrial import failure is not limited to proteotoxic insults, but that the accumulation of a nonimported metabolic enzyme elicits ectopic metabolic stress.
  • Keito Hiragi, Akira Nishide, Kenji Takagi, Kazuhiro Iwai, Minsoo Kim, Tsunehiro Mizushima
    The Journal of Biochemistry, 173(4) 317-326, Jan 4, 2023  Peer-reviewedCorresponding author
    Summary Pathogenic bacteria deliver virulence factors called effectors into host cells in order to facilitate infection. The Shigella effector proteins IpaH1.4 and IpaH2.5 are members of the “novel E3 ligase” (NEL)-type bacterial E3 ligase family. These proteins ubiquitinate the linear ubiquitin assembly complex (LUBAC) to inhibit nuclear factor (NF)-κB activation and, concomitantly, the inflammatory response. However, the molecular mechanisms underlying the interaction and recognition between IpaH1.4 and IpaH2.5 and LUBAC is unclear. Here we present the crystal structures of the substrate-recognition domains of IpaH1.4 and IpaH2.5 at resolutions of 1.4 and 3.4 Å, respectively. The LUBAC-binding site on IpaH1.4 was predicted based on structural comparisons with the structures of other NEL-type E3s. Structural and biochemical data were collected and analyzed to determine the specific residues of IpaH1.4 that are involved in interactions with LUBAC and influence NF-κB signaling. The new structural insight presented here demonstrates how bacterial pathogens target innate immune signaling pathways.
  • Akira Nishide, Kenji Takagi, Minsoo Kim, Tsunehiro Mizushima
    Feb 15, 2022  
  • Nobuo Kanazawa, Hiroaki Hemmi, Noriko Kinjo, Hidenori Ohnishi, Jun Hamazaki, Hiroyuki Mishima, Akira Kinoshita, Tsunehiro Mizushima, Satoru Hamada, Kazuya Hamada, Norio Kawamoto, Saori Kadowaki, Yoshitaka Honda, Kazushi Izawa, Ryuta Nishikomori, Miyuki Tsumura, Yusuke Yamashita, Shinobu Tamura, Takashi Orimo, Toshiya Ozasa, Takashi Kato, Izumi Sasaki, Yuri Fukuda-Ohta, Naoko Wakaki-Nishiyama, Yutaka Inaba, Kayo Kunimoto, Satoshi Okada, Takeshi Taketani, Koichi Nakanishi, Shigeo Murata, Koh-Ichiro Yoshiura, Tsuneyasu Kaisho
    Nature communications, 12(1) 6819-6819, Nov 24, 2021  Peer-reviewed
    Impaired proteasome activity due to genetic variants of certain subunits might lead to proteasome-associated autoinflammatory syndromes (PRAAS). Here we report a de novo heterozygous missense variant of the PSMB9 proteasome subunit gene in two unrelated Japanese infants resulting in amino acid substitution of the glycine (G) by aspartic acid (D) at position 156 of the encoded protein β1i. In addition to PRAAS-like manifestations, these individuals suffer from pulmonary hypertension and immunodeficiency, which are distinct from typical PRAAS symptoms. The missense variant results in impaired immunoproteasome maturation and activity, yet ubiquitin accumulation is hardly detectable in the patients. A mouse model of the heterozygous human genetic variant (Psmb9G156D/+) recapitulates the proteasome defects and the immunodeficiency phenotype of patients. Structurally, PSMB9 G156D interferes with the β-ring-βring interaction of the wild type protein that is necessary for 20S proteasome formation. We propose the term, proteasome-associated autoinflammatory syndrome with immunodeficiency (PRAAS-ID), to indicate a separate category of autoinflammatory diseases, similar to, but distinct from PRAAS, that describes the patients in this study.

Misc.

 16

Research Projects

 32