研究者業績

徳山 剛士

トクヤマ タケシ  (Tokuyama Takeshi)

基本情報

所属
自治医科大学 分子病態治療研究センター(再生医学研究部) 助教
学位
博士(生命科学)(2017年3月 東京薬科大学)

J-GLOBAL ID
201801002790088175
researchmap会員ID
B000327835

論文

 17
  • Tomohiro Hino, Satoshi N Omura, Ryoya Nakagawa, Tomoki Togashi, Satoru N Takeda, Takafumi Hiramoto, Satoshi Tasaka, Hisato Hirano, Takeshi Tokuyama, Hideki Uosaki, Soh Ishiguro, Madina Kagieva, Hiroyuki Yamano, Yuki Ozaki, Daisuke Motooka, Hideto Mori, Yuhei Kirita, Yoshiaki Kise, Yuzuru Itoh, Satoaki Matoba, Hiroyuki Aburatani, Nozomu Yachie, Tautvydas Karvelis, Virginijus Siksnys, Tsukasa Ohmori, Atsushi Hoshino, Osamu Nureki
    Cell 186(22) 4920-4935 2023年10月26日  
    SpCas9 and AsCas12a are widely utilized as genome-editing tools in human cells. However, their relatively large size poses a limitation for delivery by cargo-size-limited adeno-associated virus (AAV) vectors. The type V-F Cas12f from Acidibacillus sulfuroxidans is exceptionally compact (422 amino acids) and has been harnessed as a compact genome-editing tool. Here, we developed an approach, combining deep mutational scanning and structure-informed design, to successfully generate two AsCas12f activity-enhanced (enAsCas12f) variants. Remarkably, the enAsCas12f variants exhibited genome-editing activities in human cells comparable with those of SpCas9 and AsCas12a. The cryoelectron microscopy (cryo-EM) structures revealed that the mutations stabilize the dimer formation and reinforce interactions with nucleic acids to enhance their DNA cleavage activities. Moreover, enAsCas12f packaged with partner genes in an all-in-one AAV vector exhibited efficient knock-in/knock-out activities and transcriptional activation in mice. Taken together, enAsCas12f variants could offer a minimal genome-editing platform for in vivo gene therapy.
  • Takeshi Tokuyama, Shigeru Yanagi
    Genes 14(10) 2023年9月26日  
    Mitochondrial dynamics, including fission and fusion processes, are essential for heart health. Mitochondria, the powerhouses of cells, maintain their integrity through continuous cycles of biogenesis, fission, fusion, and degradation. Mitochondria are relatively immobile in the adult heart, but their morphological changes due to mitochondrial morphology factors are critical for cellular functions such as energy production, organelle integrity, and stress response. Mitochondrial fusion proteins, particularly Mfn1/2 and Opa1, play multiple roles beyond their pro-fusion effects, such as endoplasmic reticulum tethering, mitophagy, cristae remodeling, and apoptosis regulation. On the other hand, the fission process, regulated by proteins such as Drp1, Fis1, Mff and MiD49/51, is essential to eliminate damaged mitochondria via mitophagy and to ensure proper cell division. In the cardiac system, dysregulation of mitochondrial dynamics has been shown to cause cardiac hypertrophy, heart failure, ischemia/reperfusion injury, and various cardiac diseases, including metabolic and inherited cardiomyopathies. In addition, mitochondrial dysfunction associated with oxidative stress has been implicated in atherosclerosis, hypertension and pulmonary hypertension. Therefore, understanding and regulating mitochondrial dynamics is a promising therapeutic tool in cardiac diseases. This review summarizes the role of mitochondrial morphology in heart diseases for each mitochondrial morphology regulatory gene, and their potential as therapeutic targets to heart diseases.
  • Chika Watanabe, Hitoshi Osaka, Miyuki Watanabe, Akihiko Miyauchi, Eriko F Jimbo, Takeshi Tokuyama, Hideki Uosaki, Yoshihito Kishita, Yasushi Okazaki, Takanori Onuki, Tomohiro Ebihara, Kenichi Aizawa, Kei Murayama, Akira Ohtake, Takanori Yamagata
    Molecular genetics and metabolism reports 34 100951-100951 2023年3月  
    Coenzyme Q10 (CoQ10) is involved in ATP production through electron transfer in the mitochondrial respiratory chain complex. CoQ10 receives electrons from respiratory chain complex I and II to become the reduced form, and then transfers electrons at complex III to become the oxidized form. The redox state of CoQ10 has been reported to be a marker of the mitochondrial metabolic state, but to our knowledge, no reports have focused on the individual quantification of reduced and oxidized CoQ10 or the ratio of reduced to total CoQ10 (reduced/total CoQ10) in patients with mitochondrial diseases. We measured reduced and oxidized CoQ10 in skin fibroblasts from 24 mitochondrial disease patients, including 5 primary CoQ10 deficiency patients and 10 respiratory chain complex deficiency patients, and determined the reduced/total CoQ10 ratio. In primary CoQ10 deficiency patients, total CoQ10 levels were significantly decreased, however, the reduced/total CoQ10 ratio was not changed. On the other hand, in mitochondrial disease patients other than primary CoQ10 deficiency patients, total CoQ10 levels did not decrease. However, the reduced/total CoQ10 ratio in patients with respiratory chain complex IV and V deficiency was higher in comparison to those with respiratory chain complex I deficiency. Measurement of CoQ10 in fibroblasts proved useful for the diagnosis of primary CoQ10 deficiency. In addition, the reduced/total CoQ10 ratio may reflect the metabolic status of mitochondrial disease.
  • Razan E Ahmed, Takeshi Tokuyama, Tatsuya Anzai, Nawin Chanthra, Hideki Uosaki
    Philosophical transactions of the Royal Society of London. Series B, Biological sciences 377(1864) 20210325-20210325 2022年11月21日  
    During postnatal cardiac development, cardiomyocytes mature and turn into adult ones. Hence, all cellular properties, including morphology, structure, physiology and metabolism, are changed. One of the most important aspects is the contractile apparatus, of which the minimum unit is known as a sarcomere. Sarcomere maturation is evident by enhanced sarcomere alignment, ultrastructural organization and myofibrillar isoform switching. Any maturation process failure may result in cardiomyopathy. Sarcomere function is intricately related to other organelles, and the growing evidence suggests reciprocal regulation of sarcomere and mitochondria on their maturation. Herein, we summarize the molecular mechanism that regulates sarcomere maturation and the interplay between sarcomere and other organelles in cardiomyocyte maturation. This article is part of the theme issue 'The cardiomyocyte: new revelations on the interplay between architecture and function in growth, health, and disease'.
  • Takeshi Tokuyama, Hideki Uosaki, Ayumu Sugiura, Gen Nishitai, Keisuke Takeda, Shun Nagashima, Isshin Shiiba, Naoki Ito, Taku Amo, Satoshi Mohri, Akiyuki Nishimura, Motohiro Nishida, Ayumu Konno, Hirokazu Hirai, Satoshi Ishido, Takahiro Yoshizawa, Takayuki Shindo, Shingo Takada, Shintaro Kinugawa, Ryoko Inatome, Shigeru Yanagi
    iScience 25(7) 104582-104582 2022年7月15日  
    Abnormal mitochondrial fragmentation by dynamin-related protein1 (Drp1) is associated with the progression of aging-associated heart diseases, including heart failure and myocardial infarction (MI). Here, we report a protective role of outer mitochondrial membrane (OMM)-localized E3 ubiquitin ligase MITOL/MARCH5 against cardiac senescence and MI, partly through Drp1 clearance by OMM-associated degradation (OMMAD). Persistent Drp1 accumulation in cardiomyocyte-specific MITOL conditional-knockout mice induced mitochondrial fragmentation and dysfunction, including reduced ATP production and increased ROS generation, ultimately leading to myocardial senescence and chronic heart failure. Furthermore, ischemic stress-induced acute downregulation of MITOL, which permitted mitochondrial accumulation of Drp1, resulted in mitochondrial fragmentation. Adeno-associated virus-mediated delivery of the MITOL gene to cardiomyocytes ameliorated cardiac dysfunction induced by MI. Our findings suggest that OMMAD activation by MITOL can be a therapeutic target for aging-associated heart diseases, including heart failure and MI.

共同研究・競争的資金等の研究課題

 2

産業財産権

 1