OTSUBO Yoshitaka

写真a

Title

Associate Professor

Laboratory

2-4 Hibikino, Wakamatsu-ku, Kitakyushu-shi, Fukuoka

Research Fields, Keywords

Degree 【 display / non-display

  • Kyushu Institute of Technology -  Doctor of Information Engineering  2001.06

Biography in Kyutech 【 display / non-display

  • 2014.04
    -
    Now

    Kyushu Institute of TechnologyGraduate School of Life Science and Systems Engineering   Department of Human Intelligence Systems   Associate Professor  

  • 2012.04
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    2014.03

    Kyushu Institute of TechnologyGraduate School of Life Science and Systems Engineering   Department of Brain Science and Engineering   Associate Professor  

  • 2007.04
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    2012.03

    Kyushu Institute of TechnologyGraduate School of Life Science and Systems Engineering   Assistant Professor  

Academic Society Memberships 【 display / non-display

  • 2009.09
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    Now
     

    The Japanese Association for the Study of Taste and Smell  JAPAN

  • 2009.09
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    Now
     

    Physiological Society of Japan  JAPAN

  • 2007.07
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    Now
     

    The Japan Neuroscience Society  JAPAN

  • 2002.10
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    Now
     

    Society for Neuroscience  UNITED STATES

 

Publications (Article) 【 display / non-display

  • Quantitative analysis of taste bud cell numbers in the circumvallate and foliate taste buds of mice

    Takahiro Ogata, Yoshitaka Ohtubo

    Chemical Senses  ( Oxford University Press )    2020.03  [Refereed]

     View Summary

    A mouse single taste bud contains 10–100 taste bud cells (TBCs) in which the elongated TBCs are classified into three cell types (types I–III) equipped with different taste receptors. Accordingly, differences in the cell numbers and ratios of respective cell types per taste bud may affect taste nerve responsiveness. Here we examined the numbers of each immunoreactive cell for the type II (sweet, bitter, or umami receptor cells) and type III (sour and/or salt receptor cells) markers per taste bud in the circumvallate and foliate papillae, and compared these numerical features of TBCs per taste bud to those in fungiform papilla and soft palate, which we previously reported. In circumvallate and foliate taste buds, the numbers of TBCs and immunoreactive cells per taste bud increased as a linear function of the maximal cross-sectional taste bud area. Type II cells made up approximately 25% of TBCs irrespective of the regions from which the TBCs arose. In contrast, type III cells in circumvallate and foliate taste buds made up approximately 11% of TBCs, which represented almost two-times higher than what was observed in the fungiform and soft palate taste buds. The densities (number of immunoreactive cells per taste bud divided by the maximal cross-sectional area of the taste bud) of types II and III cells per taste bud are significantly higher in the circumvallate papillae than in the other regions. The effects of these region-dependent differences on the taste response of the taste bud are discussed.

    DOI PubMed

  • A subset of taste receptor cells express biocytin-permeable channels activated by reducing extracellular Ca2+ concentration

    Masafumi Iwamoto, Madoka Takashima, Yoshitaka Ohtubo

    European Journal of Neuroscience  ( Blackwell Publishing Ltd )    2020.01  [Refereed]

     View Summary

    Taste receptor cells (type II cells) transmit taste information to taste nerve fibres via ATP‐permeable channels, including calcium homeostasis modulator (CALHM), connexin and/or pannexin1 channels, via the paracrine release of adenosine triphosphate (ATP) as a predominant transmitter. In the present study, we demonstrate that extracellular Ca2+‐dependent biocytin‐permeable channels are present in a subset of type II cells in mouse fungiform taste buds using biocytin uptake, immunohistochemistry and in situ whole‐cell recordings. Type II cells were labelled with biocytin in an extracellular Ca2+ concentration ([Ca2+]out)‐sensitive manner. We found that the ratio of biocytin‐labelled type II cells to type II cells per taste bud was approximately 20% in 2 mM Ca2+ saline, and this ratio increased to approximately 50% in nominally Ca2+‐free saline. The addition of 300 µM GdCl3, which inhibits various channels including CALHM1 channels, significantly inhibited biocytin labelling in nominally Ca2+‐free saline, whereas the addition of 20 µM ruthenium red did not. Moreover, Cs+‐insensitive currents increased in nominally Ca2+‐free saline in approximately 40% of type II cells. These increased currents appeared at a potential of above −35 mV, reversed at approximately +10 mV and increased with depolarization. These results suggest that biocytin labels type II cells via ion channels activated by [Ca2+]out reduction, probably “CALHM‐like” channels, on the basolateral membrane and that taste receptor cells can be categorized into two groups based on differences in the expression levels of [Ca2+]out‐dependent biocytin‐permeable channels. These data indicate electrophysiological and pharmacologically relevant properties of biocytin‐permeable channels and suggest their contributions to taste signal transduction.

    DOI PubMed

  • Counting algorithm for sequential optical images of immunoreactive mouse taste bud cells

    Katsumi Tateno, Osamu Shiku, Yoshitaka Ohtubo

    ICIC Express Letters  ( ICIC International )  14 ( 1 ) 1 - 8   2020.01  [Refereed]

     View Summary

    We developed a counting algorithm for use with sequential optical images of immunoreactive mouse taste bud cells. To count the immunoreactive cells in serial thin sections, continuity of a cell through the sequential sections must be confirmed. For this purpose, we used the overlap ratio of the cell regions in given sections and the distance between the sections. Results show that the mean positive predictive value for mouse taste bud cells was 99%; the mean sensitivity was 73%. Gamma correction improved the mean sensitivity to 87% with a slight decrease in the mean positive predictive value (94%).

    DOI

  • Voltage-gated channels and neurotransmitter receptors in mouse taste bud cells

      25 ( 1 ) 25 - 34   2018.04

  • Selective expression of muscarinic acetylcholine receptor subtype M3 by mouse type III taste bud cells

    Yusuke Mori, Kohgaku Eguchi, Kiyonori Yoshii, and Yoshitaka Ohtubo

    Pflugers Archiv -European Journal of Physiology    468 ( 11 ) 2053 - 2059   2016.11  [Refereed]

    DOI

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Conference Prsentations (Oral, Poster) 【 display / non-display

  • Immunohistostaining and Ca2+-imaging of tracheal solitary chemosensory cells in mice

    Ohtubo Yoshitaka, Miyazaki Aiko

    第97回日本生理学会大会  (誌上開催)  2020.03  -  2020.03  日本生理学会

  • Numerical studies on the expression of cell type marker proteins in mouse circumvallate taste buds.

    The 48th Annual Meeting of the Japanese Association for the Study of Taste and Smell  2014.10  -  2014.10 

  • Density of taste receptor cell types in mouse circumvallate taste buds.

    Ohtubo Y

    XXIVth International Conference of European Chemoreception Research Organization  (Dijon, France)  2014.09  -  2014.09 

  • Aging-dependent changes in the ratio between taste receptor cells in ~20-month-old mice

    Y. Higure, Y. Ohtubo, K. Yoshii

    FENS Featured Regional Meeting  (Prague, Czech Republic)  2013.09  -  2013.09 

  • Aging effects on electrophysiological properties of taste receptor cells in ~20-month-old mice.

    K. Takeuchi, Y. Ohtubo, K. Yoshii

    FENS Featured Regional Meeting  (Prague, Czech Republic)  2013.09  -  2013.09 

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Honors and Awards 【 display / non-display

  • Outstanding Poster Award

    2006.09.08     SPAIN

    Winner: K. Kimura,Y. Ohtubo,T. Kumazawa and K. Yoshii

 

Activities of Academic societies and Committees 【 display / non-display

  • 2018.01
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    2020.12

    The Japanese Association for the Study of Taste and Smell  

  • 2015.01
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    2017.12

    The Japanese Association for the Study of Taste and Smell  

  • 2014.04
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    Now

    The Japanese Association for the Study of Taste and Smell