Updated on 2021/06/22

写真b

 
OKA Toshihiko
 
*Items subject to periodic update by Rikkyo University (The rest are reprinted from information registered on researchmap.)
Affiliation*
College of Science Department of Life Science
Graduate School of Science Field of Study: Life Science
Graduate School of Science Field of Study: Life Science
Title*
Professor
Degree
博士(理学) ( 東京大学 ) / PhD (Science) ( The University of Tokyo )
Research Theme*
  • 細胞小器官(オルガネラ)はそれぞれ固有の機能と形態をもっている。オルガネラの機能は細胞の生存にとって必須だが、オルガネラの形態は細胞やオルガネラの機能にとってどのような役割があるのか?この命題を、細胞内のエネルギー産生の場であるミトコンドリアに着目し、分子生物学や生化学的手法を用いて、その膜形態の形成と制御機構を理解することで、オルガネラ形態の生理的意義の解明をめざしている。

  • Campus Career*
    • 4 2012 - Present 
      College of Science   Department of Life Science   Professor
    • 4 2012 - Present 
      Graduate School of Science   Field of Study: Life Science   Professor
    • 4 2012 - Present 
      Graduate School of Science   Field of Study: Life Science   Professor
     

    Research Areas

    • Life Science / Cell biology

    Research History

    • 4 2012 - Present 
      RIKKYO UNIVERSITY   Graduate School of Science Field of Study: Life Science   Professor

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    • 4 2012 - Present 
      RIKKYO UNIVERSITY   College of Science Department of Life Science   Professor

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    • 4 2012 - Present 
      RIKKYO UNIVERSITY   Graduate School of Science Field of Study: Life Science   Professor

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    Education

    • 4 1991 - 3 1994 
      The University of Tokyo   Graduate School, Division of Science

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      Country: Japan

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    • 4 1991 - 3 1994 
      The University of Tokyo   Graduate School, Division of Science

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      Country: Japan

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    • 4 1989 - 3 1991 
      The University of Tokyo   Graduate School, Division of Science

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      Country: Japan

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    • 4 1989 - 3 1991 
      The University of Tokyo   Graduate School, Division of Science

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      Country: Japan

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    • 4 1985 - 3 1989 
      Kyushu University   Faculty of Science   Department of Biology

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      Country: Japan

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    Papers

    • Concentration of mitochondrial DNA mutations by cytoplasmic transfer from platelets to cultured mouse cells. Peer-reviewed

      Ishikawa, K, K. Kobayashi, A. Yamada, M. Umehara, T. Oka, K. Nakada

      PLOS ONE   2019

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      Language:English   Publishing type:Research paper (scientific journal)  

      DOI: 10.1371/journal.pone.0213283

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    • Inactivation of cardiolipin synthase triggers changes in mitochondrial morphology Peer-reviewed

      Ayaka Matsumura, Jun Higuchi, Yasunori Watanabe, Masahiro Kato, Keigo Aoki, Shiori Akabane, Toshiya Endo, Toshihiko Oka

      FEBS Letters592 ( 2 ) 209 - 218   1 1 2018

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:Wiley Blackwell  

      Mitochondrial tubular structures are maintained by a balance between membrane fusion and fission that is regulated by various factors, including Drp1 and mitofusin/fzo-1. Here we report the role of cardiolipin (CL) synthase in the regulation of mitochondrial morphology. Knockdown of CL synthase induced mitochondrial elongation in nematode and human cells. Knockdown of both nematode cardiolipin synthase and drp-1 or fzo-1 suggested that knocking down CL synthase decreases mitochondrial division. Mass spectrometric analysis of human CL synthase-knocked down cells revealed a decreased amount of CL and an accumulation of phosphatidylglycerol, a CL precursor. Knockdown of other genes involved in CL synthesis did not influence mitochondrial morphology. Thus, mitochondrial elongation may result from the accumulation of phosphatidylglycerol rather than decreased CL.

      DOI: 10.1002/1873-3468.12948

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    • In vitro synthesis of the human calcium transporter Letm1 within cell-sized liposomes and investigation of its lipid dependency Peer-reviewed

      Okamura, K, S. Matsushita, Y. Kato, H. Watanabe, A. Matsui, T. Oka, T. Matsuura

      J. Biosci. Bioeng.   2018

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      Language:English   Publishing type:Research paper (scientific journal)  

      DOI: 10.1016/j.jbiosc.2018.11.003

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    • Structural insights into ubiquitin phosphorylation by PINK1 Peer-reviewed

      Okatsu, K, Y. Sato, K. Yamano, N. Matsuda, L. Negishi, A. Takahashi, A. Yamagata, S. Goto-Ito, M. Mishima, Y. Ito, T. Oka, K. Tanaka, S. Fukai

      Sci. Rep.   2018

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      Language:English   Publishing type:Research paper (scientific journal)  

      DOI: 10.1038/s41598-018-28656-8

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    • Molecular basis of selective mitochondrial fusion by heterotypic action between OPA1 and cardiolipin. Peer-reviewed

      Ban, T, T. Ishihara, H. Kohno, S. Saita, A. Ichimura, K. Maenaka, T. Oka, K. Mihara, N. Ishihara

      Nat. Cell Biol.   2017

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      Language:English   Publishing type:Research paper (scientific journal)  

      DOI: 10.1038/ncb356

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    • Constitutive Activation of PINK1 Protein Leads to Proteasome-mediated and Non-apoptotic Cell Death Independently of Mitochondrial Autophagy Peer-reviewed

      Shiori Akabane, Kohei Matsuzaki, Shun-ichi Yamashita, Kana Arai, Kei Okatsu, Tomotake Kanki, Noriyuki Matsuda, Toshihiko Oka

      JOURNAL OF BIOLOGICAL CHEMISTRY291 ( 31 ) 16162 - 16174   7 2016

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER SOC BIOCHEMISTRY MOLECULAR BIOLOGY INC  

      Phosphatase and tensin homolog-induced putative kinase 1 (PINK1), a Ser/Thr kinase, and PARKIN, a ubiquitin ligase, are causal genes for autosomal recessive early-onset parkinsonism. Multiple lines of evidence indicate that PINK1 and PARKIN cooperatively control the quality of the mitochondrial population via selective degradation of damaged mitochondria by autophagy. Here, we report that PINK1 and PARKIN induce cell death with a 12-h delay after mitochondrial depolarization, which differs from the time profile of selective autophagy of mitochondria. This type of cell death exhibited definite morphologic features such as plasma membrane rupture, was insensitive to a pan-caspase inhibitor, and did not involve mitochondrial permeability transition. Expression of a constitutively active form of PINK1 caused cell death in the presence of a pan-caspase inhibitor, irrespective of the mitochondrial membrane potential. PINK1-mediated cell death depended on the activities of PARKIN and proteasomes, but it was not affected by disruption of the genes required for autophagy. Furthermore, fluorescence and electron microscopic analyses revealed that mitochondria were still retained in the dead cells, indicating that PINK1-mediated cell death is not caused by mitochondrial loss. Our findings suggest that PINK1 and PARKIN play critical roles in selective cell death in which damaged mitochondria are retained, independent of mitochondrial autophagy.

      DOI: 10.1074/jbc.M116.714923

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    • PKA Regulates PINK1 Stability and Parkin Recruitment to Damaged Mitochondria through Phosphorylation of MIC60 Peer-reviewed

      Shiori Akabane, Midori Uno, Naoki Tani, Shunta Shimazaki, Natsumi Ebara, Hiroki Kato, Hidetaka Kosako, Toshihiko Oka

      MOLECULAR CELL62 ( 3 ) 371 - 384   5 2016

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:CELL PRESS  

      A mitochondrial kinase, PTEN-induced putative kinase 1 (PINK1), selectively recruits the ubiquitin ligase Parkin to damaged mitochondria, which modifies mitochondria by polyubiquitination, leading to mitochondrial autophagy. Here, we report that treatment with an adenylate cyclase agonist or expression of protein kinase A (PKA) impairs Parkin recruitment to damaged mitochondria and decreases PINK1 protein levels. We identified a mitochondrial membrane protein, MIC60 (also known as mitofilin), as a PKA substrate. Mutational and mass spectrometric analyses revealed that the Ser528 residue of MIC60 undergoes PKA-dependent phosphorylation. MIC60 transiently interacts with PINK1, and MIC60 downregulation leads to a reduction in PINK1 and mislocalization of Parkin. Phosphorylation-mimic mutants of MIC60 fail to restore the defect in Parkin recruitment in MIC60-knocked down cells, whereas a phosphorylation-deficient MIC60 mutant facilitates the mitochondrial localization of Parkin. Our findings indicate that PKA-mediated phosphorylation of MIC60 negatively regulates mitochondrial clearance that is initiated by PINK1 and Parkin.

      DOI: 10.1016/j.molcel.2016.03.037

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    • Unconventional PINK1 localization to the outer membrane of depolarized mitochondria drives Parkin recruitment Peer-reviewed

      Kei Okatsu, Mayumi Kimura, Toshihiko Oka, Keiji Tanaka, Noriyuki Matsuda

      JOURNAL OF CELL SCIENCE128 ( 5 ) 964 - 978   3 2015

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:COMPANY OF BIOLOGISTS LTD  

      Dysfunction of PTEN-induced putative kinase 1 (PINK1), a Ser/Thr kinase with an N-terminal mitochondrial-targeting sequence (MTS), causes familial recessive parkinsonism. Reduction of the mitochondrial membrane potential limits MTS-mediated matrix import and promotes PINK1 accumulation on the outer mitochondrial membrane (OMM) of depolarized mitochondria. PINK1 then undergoes autophosphorylation and phosphorylates ubiquitin and Parkin, a cytosolic ubiquitin ligase, for clearance of damaged mitochondria. The molecular basis for PINK1 localization on the OMM of depolarized mitochondria rather than release to the cytosol is poorly understood. Here, we disentangle the PINK1 localization mechanism using deletion mutants and a newly established constitutively active PINK1 mutant. Disruption of the MTS through N-terminal insertion of aspartic acid residues results in OMM localization of PINK1 in energized mitochondria. Unexpectedly, the MTS and putative transmembrane domain (TMD) are dispensable for OMM localization, whereas mitochondrial translocase Tom40 (also known as TOMM40) and an alternative mitochondrial localization signal that resides between the MTS and TMD are required. PINK1 utilizes a mitochondrial localization mechanism that is distinct from that of conventional MTS proteins and that presumably functions in conjunction with the Tom complex in OMM localization when the conventional N-terminal MTS is inhibited.

      DOI: 10.1242/jcs.161000

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    • A dimeric pink1-containing complex on depolarized mitochondria stimulates parkin recruitment Peer-reviewed

      Kei Okatsu, Midori Uno, Fumika Koyano, Etsu Go, Mayumi Kimura, Toshihiko Oka, Keiji Tanaka, Noriyuki Matsuda

      Journal of Biological Chemistry288 ( 51 ) 36372 - 36384   20 12 2013

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      Language:English   Publishing type:Research paper (scientific journal)  

      Parkinsonism typified by sporadic Parkinson disease is a prevalent neurodegenerative disease. Mutations in PINK1 (PTENinduced putative kinase 1), a mitochondrial Ser/Thr protein kinase, or PARKIN, a ubiquitin-protein ligase, cause familial parkinsonism. The accumulation and autophosphorylation of PINK1 on damaged mitochondria results in the recruitment of Parkin, which ultimately triggers quarantine and/or degradation of the damaged mitochondria by the proteasome and autophagy. However, the molecular mechanism of PINK1 in dissipation of the mitochondrial membrane potential (ΔΨm) has not been fully elucidated. Here we show by fluorescence-based techniques that the PINK1 complex formed following a decrease in ΔΨm is composed of two PINK1 molecules and is correlated with intermolecular phosphorylation of PINK1. Disruption of complex formation by the PINK1 S402A mutation weakened Parkin recruitment onto depolarized mitochondria. The most disease-relevant mutations of PINK1 inhibit the complex formation. Taken together, these results suggest that formation of the complex containing dyadic PINK1 is an important step for Parkin recruitment onto damaged mitochondria. © 2013 by The American Society for Biochemistry and Molecular Biology.

      DOI: 10.1074/jbc.M113.509653

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    • Fis1 acts as a mitochondrial recruitment factor for TBC1D15 that is involved in regulation of mitochondrial morphology. Peer-reviewed International journal

      Kenta Onoue, Akihiro Jofuku, Reiko Ban-Ishihara, Takaya Ishihara, Maki Maeda, Takumi Koshiba, Takashi Itoh, Mitsunori Fukuda, Hidenori Otera, Toshihiko Oka, Hiroyoshi Takano, Noboru Mizushima, Katsuyoshi Mihara, Naotada Ishihara

      Journal of cell science126 ( Pt 1 ) 176 - 85   1 1 2013

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      Language:English   Publishing type:Research paper (scientific journal)  

      In yeast, C-tail-anchored mitochondrial outer membrane protein Fis1 recruits the mitochondrial-fission-regulating GTPase Dnm1 to mitochondrial fission sites. However, the function of its mammalian homologue remains enigmatic because it has been reported to be dispensable for the mitochondrial recruitment of Drp1, a mammalian homologue of Dnm1. We identified TBC1D15 as a Fis1-binding protein in HeLa cell extracts. Immunoprecipitation revealed that Fis1 efficiently interacts with TBC1D15 but not with Drp1. Bacterially expressed Fis1 and TBC1D15 formed a direct and stable complex. Exogenously expressed TBC1D15 localized mainly in cytoplasm in HeLa cells, but when coexpressed with Fis1 it localized to mitochondria. Knockdown of TBC1D15 induced highly developed mitochondrial network structures similar to the effect of Fis1 knockdown, suggesting that the TBC1D15 and Fis1 are associated with the regulation of mitochondrial morphology independently of Drp1. These data suggest that Fis1 acts as a mitochondrial receptor in the recruitment of mitochondrial morphology protein in mammalian cells.

      DOI: 10.1242/jcs.111211

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    • PINK1 autophosphorylation upon membrane potential dissipation is essential for Parkin recruitment to damaged mitochondria Peer-reviewed

      Kei Okatsu, Toshihiko Oka, Masahiro Iguchi, Kenji Imamura, Hidetaka Kosako, Naoki Tani, Mayumi Kimura, Etsu Go, Fumika Koyano, Manabu Funayama, Kahori Shiba-Fukushima, Shigeto Sato, Hideaki Shimizu, Yuko Fukunaga, Hisaaki Taniguchi, Masaaki Komatsu, Nobutaka Hattori, Katsuyoshi Mihara, Keiji Tanaka, Noriyuki Matsuda

      NATURE COMMUNICATIONS3   8 2012

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:NATURE PUBLISHING GROUP  

      Dysfunction of PINK1, a mitochondrial Ser/Thr kinase, causes familial Parkinson's disease (PD). Recent studies have revealed that PINK1 is rapidly degraded in healthy mitochondria but accumulates on the membrane potential (Delta Psi m)-deficient mitochondria, where it recruits another familial PD gene product, Parkin, to ubiquitylate the damaged mitochondria. Despite extensive study, the mechanism underlying the homeostatic control of PINK1 remains unknown. Here we report that PINK1 is autophosphorylated following a decrease in Delta Psi mm and that most disease-relevant mutations hinder this event. Mass spectrometric and mutational analyses demonstrate that PINK1 autophosphorylation occurs at Ser228 and Ser402, residues that are structurally clustered together. Importantly, Ala mutation of these sites abolishes autophosphorylation of PINK1 and inhibits Parkin recruitment onto depolarized mitochondria, whereas Asp (phosphorylation-mimic) mutation promotes mitochondrial localization of Parkin even though autophosphorylation was still compromised. We propose that autophosphorylation of Ser228 and Ser402 in PINK1 is essential for efficient mitochondrial localization of Parkin.

      DOI: 10.1038/ncomms2016

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    • KLP6: a newly identified kinesin that regulates the morphology and transport of mitochondria in neuronal cells Peer-reviewed

      Kousuke Tanaka, Yoshimi Sugiura, Ryohei Ichishita, Katsuyoshi Mihara, Toshihiko Oka

      JOURNAL OF CELL SCIENCE124 ( 14 ) 2457 - 2465   7 2011

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:COMPANY OF BIOLOGISTS LTD  

      Mitochondria utilize diverse cytoskeleton-based mechanisms to control their functions and morphology. Here, we report a role for kinesin-like protein KLP6, a newly identified member of the kinesin family, in mitochondrial morphology and dynamics. An RNA interference screen using Caenorhabditis elegans led us to identify a C. elegans KLP-6 involved in maintaining mitochondrial morphology. We cloned a cDNA coding for a rat homolog of C. elegans KLP-6, which is an uncharacterized kinesin in vertebrates. A rat KLP6 mutant protein lacking the motor domain induced changes in mitochondrial morphology and significantly decreased mitochondrial motility in HeLa cells, but did not affect the morphology of other organelles. In addition, the KLP6 mutant inhibited transport of mitochondria during anterograde movement in differentiated neuro 2a cells. To date, two kinesins, KIF1B alpha and kinesin heavy chain (KHC; also known as KIF5) have been shown to be involved in the distribution of mitochondria in neurons. Expression of the kinesin heavy chain/KIF5 mutant prevented mitochondria from entering into neurites, whereas both the KLP6 and KIF1B alpha mutants decreased mitochondrial transport in axonal neurites. Furthermore, both KLP6 and KIF1B alpha bind to KBP, a KIF1-binding protein required for axonal outgrowth and mitochondrial distribution. Thus, KLP6 is a newly identified kinesin family member that regulates mitochondrial morphology and transport.

      DOI: 10.1242/jcs.086470

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    • Identification of a novel protein MICS1 that is involved in maintenance of mitochondrial morphology and apoptotic release of cytochrome c Peer-reviewed

      Toshihiko Oka, Tomoko Sayano, Shoko Tamai, Sadaki Yokota, Hiroki Kato, Gen Fujii, Katsuyoshi Mihara

      MOLECULAR BIOLOGY OF THE CELL19 ( 6 ) 2597 - 2608   6 2008

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:AMER SOC CELL BIOLOGY  

      Mitochondrial morphology dynamically changes in a balance of membrane fusion and fission in response to the environment, cell cycle, and apoptotic stimuli. Here, we report that a novel mitochondrial protein, MICS1, is involved in mitochondrial morphology in specific cristae structures and the apoptotic release of cytochrome c from the mitochondria. MICS1 is an inner membrane protein with a cleavable presequence and multiple transmembrane segments and belongs to the Bi-1 super family. MICS1 down-regulation causes mitochondrial fragmentation and cristae disorganization and stimulates the release of proapoptotic proteins. Expression of the anti-apoptotic protein Bcl-XL does not prevent morphological changes of mitochondria caused by MICS1 down-regulation, indicating that MICS1 plays a role in maintaining mitochondrial morphology separately from the function in apoptotic pathways. MICS1 overproduction induces mitochondrial aggregation and partially inhibits cytochrome c release during apoptosis, regardless of the occurrence of Bax targeting. MICS1 is cross-linked to cytochrome c without disrupting membrane integrity. Thus, MICS1 facilitates the tight association of cytochrome c with the inner membrane. Furthermore, under low-serum condition, the delay in apoptotic release of cytochrome c correlates with MICS1 up-regulation without significant changes in mitochondrial morphology, suggesting that MICS1 individually functions in mitochondrial morphology and cytochrome c release.

      DOI: 10.1091/mbc.E07-12-1205

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    • An RNAi screen for mitochondrial proteins required to maintain the morphology of the organelle in C. elegans. Peer-reviewed

      Ichishita, R, K. Tanaka, Y. Sugiura, T. Sayano, K. Mihara, T. Oka

      J. Biochem.   2008

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      Language:English   Publishing type:Research paper (scientific journal)  

      DOI: 10.1093/jb/mvm245

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    • Characterization of the mitochondrial protein LETM1, which maintains the mitochondrial tubular shapes and interacts with an AAA-ATPase BCS1L. Peer-reviewed

      Tamai, S, H. Iida, S. Yokota, T. Sayano, S. Kiguchiya, N. Ishihara, J.-I. Hayashi, K. Mihara, T. Oka

      J. Cell Sci.   2008

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      Language:English   Publishing type:Research paper (scientific journal)  

      DOI: 10.1242/jcs.026625

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    • Inhibition of GTP hydrolysis by Sar1p causes accumulation of vesicles that are a functional intermediate of the ER-to-Golgi transport in yeast Peer-reviewed

      Toshihiko Oka, Akihiko Nakano

      Journal of Cell Biology124 ( 4 ) 425 - 434   1994

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      Language:English   Publishing type:Research paper (scientific journal)   Publisher:Rockefeller University Press  

      The SAR1 gene product (Sar1p), a 21-kD GTPase, is a key component of the ER-to-Golgi transport in the budding yeast. We previously reported that the in vitro reconstitution of protein transport from the ER to the Golgi was dependent on Sar1p and Sec12p (Oka, T., S. Nishikawa, and A. Nakano. 1991. J. Cell Biol. 114:671-679). Sec12p is an integral membrane protein in the ER and is essential for the Sar1 function. In this paper, we show that Sar1p can remedy the temperature-sensitive defect of the sec12 mutant membranes, which is in the formation of ER-to-Golgi transport vesicles. The addition of Sar1p promotes vesicle formation from the ER irrespective of the GTP- or GTPγS- bound form, indicating that the active form of Sar1p but not the hydrolysis of GTP is required for this process. The inhibition of GTP hydrolysis blocks transport of vesicles to the Golgi and thus causes their accumulation. The accumulating vesicles, which carry Sar1p on them, can be separated from other membranes, and, after an appropriate wash that removes Sar1p, are capable of delivering the content to the Golgi when added back to fresh membranes. Thus we have established a new method for isolation of functional intermediate vesicles in the ER-to-Golgi transport. The sec23 mutant is defective in activation of Sar1 GTPase (Yoshihisa, T., C. Barlowe, and R. Schekman. 1993. Science (Wash. DC). 259:1466-1468). The membranes and cytosol from the sec23 mutant show only a partial defect in vesicle formation and this defect is also suppressed by the increase of Sar1p. Again GTP hydrolysis is not needed for the suppression of the defect in vesicle formation. Based on these results, we propose a model in which Sar1p in the GTP-bound form is required for the formation of transport vesicles from the ER and the GTP hydrolysis by Sar1p is essential for entering the next step of vesicular transport to the Golgi apparatus.

      DOI: 10.1083/jcb.124.4.425

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    Misc.

    • PKAはMIC60のリン酸化を介してPINK1とParkinによるミトコンドリア品質管理を制御する Invited

      赤羽しおり, 岡 敏彦

      実験医学   2016

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      Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)  

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    • ミトコンドリア形態異常と疾患 Invited

      岡 敏彦

      医学のあゆみ   2015

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      Language:Japanese   Publishing type:Article, review, commentary, editorial, etc. (trade magazine, newspaper, online media)  

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    • Regulation and Physiologic Functions of GTPases in Mitochondrial Fusion and Fission in Mammals Invited Peer-reviewed

      Naotada Ishihara, Hidenori Otera, Toshihiko Oka, Katsuyoshi Mihara

      ANTIOXIDANTS & REDOX SIGNALING19 ( 4 ) 389 - 399   8 2013

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      Language:English   Publishing type:Book review, literature introduction, etc.   Publisher:MARY ANN LIEBERT, INC  

      Significance: Mitochondria are double membrane-bound organelles with tubular network structures that are essential for oxidative ATP production and play pivotal roles in regulating calcium homeostasis and apoptosis. Furthermore, mitochondria produce large amounts of reactive oxygen species that are fatal to cellular functions through uncoupled respiration. These organelles dynamically change their morphology by frequent fusion and fission, and three types of high molecular weight GTPase proteins have been identified as core components of the fusion and fission machineries. Recent Advances: Here, we review recent advances in the study of mitochondrial fission and fusion GTPases and their physiologic roles in mammalian cells. The regulation of mitochondrial dynamics coupled with a quality control system is essential for cellular homeostasis, development, and tissue differentiation. Defects of these mechanisms cause various disorders, including neurodegenerative diseases, such as Parkinson's disease, Huntington's disease, and Alzheimer's disease. Critical Issues: Although a significant amount of relevant data has accumulated on the regulation of mammalian mitochondrial fusion and fission, mechanistic molecular details and cellular functions still remain insufficiently defined. Future Directions: Elucidating the physiologic roles of mitochondrial fusion and fission in highly differentiated cells using tissue-specific knockout mice remains a challenge for the future.

      DOI: 10.1089/ars.2012.4830

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    • ミトコンドリア膜構造変化とアポトーシス制御 Invited

      大寺秀典, 岡 敏彦

      細胞工学   2010

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    • Retrograde transport on the COG railway Invited Peer-reviewed

      D Ungar, T Oka, M Krieger, FM Hughson

      TRENDS IN CELL BIOLOGY16 ( 2 ) 113 - 120   2 2006

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      Language:English   Publishing type:Book review, literature introduction, etc.   Publisher:ELSEVIER SCIENCE LONDON  

      The conserved oligomeric Golgi (COG) complex is essential for establishing and/or maintaining the structure and function of the Golgi apparatus. The Golgi apparatus, in turn, has a central role in protein sorting and glycosylation within the eukaryotic secretory pathway. As a consequence, COG mutations can give rise to human genetic diseases known as congenital disorders of glycosylation. We review recent results from studies of yeast, worm, fly and mammalian COG that provide evidence that COG might function in retrograde vesicular trafficking within the Golgi apparatus. This hypothesis explains the impact of COG mutations by postulating that they impair the retrograde flow of resident Golgi proteins needed to maintain normal Golgi structure and function.

      DOI: 10.1016/j.tcb.2005.12.004

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    • A railroad switch in mitochondrial protein import Invited

      T Oka, K Mihara

      MOLECULAR CELL18 ( 2 ) 145 - 146   4 2005

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      Language:English   Publishing type:Other   Publisher:CELL PRESS  

      Chacinska et al. (2005) recently clarified how translocation machineries of the mitochondrial outer and inner membranes cooperate to correctly sort preproteins destined for the mitochondrial matrix and inner membrane.

      DOI: 10.1016/j.molcel.2005.03.022

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    • Multi-component protein complexes and Golgi membrane trafficking. Invited Peer-reviewed

      Oka, T, M. Krieger

      J. Biochem.   2005

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      Language:English   Publishing type:Article, review, commentary, editorial, etc. (scientific journal)  

      DOI: 10.1093/jb/mvi024

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