SARATANI, Yuya

写真a

Affiliation

Faculty of Science and Engineering, School of Advanced Science and Engineering

Job title

Assistant Professor(without tenure)

Degree 【 display / non-display

  • 2021.03   早稲田大学   博士 (理学)

Professional Memberships 【 display / non-display

  • 2017.09
    -
    Now

    日本比較生理生化学会

  • 2016.10
    -
    Now

    日本動物学会

 

Research Areas 【 display / non-display

  • Animal physiological chemistry, physiology and behavioral biology   光生物学

Research Interests 【 display / non-display

  • 小型魚類

  • 動物行動学

  • 光生物学

Papers 【 display / non-display

  • Clock Gene Expression in the Eye Exhibits Circadian Oscillation and Light Responsiveness but is Not Necessary for Nocturnal Locomotor Activity of Japanese Loach, Misgurnus anguillicaudatus.

    Yuya Saratani, Yuki Takeuchi, Keiko Okano, Toshiyuki Okano

    Zoological science   37 ( 2 ) 177 - 192  2020.04  [Domestic journal]

     View Summary

    There are few model fish that are both edible and suitable for use in the laboratory. The Japanese loach (Misgurnus anguillicaudatus) is a traditional food in Japan, but is highly neglected despite its great nutritional value. To understand its circadian system and photic input pathway for synchronization of physiological activities to environmental light-dark cycles, we measured locomotor activity under light-dark and constant dark (DD) conditions. Locomotor activity was found to be higher in the nighttime than daytime, and its rhythmicity was weakened under DD conditions. The nocturnal activity of the Japanese loach is mainly controlled by environmental light, rather than the circadian clock. We explored the circadian regulation and light-responsiveness of clock gene expression in the eyes of loaches. The daily expression profiles of its mRNA revealed that most of the examined Cry and Per genes were likely regulated by internal circadian and/or environmental light signals. Among the Opsin genes transcribed in the eye, we detected the retinal photopigment porphyropsin at the protein level, which was lower than in mice. This property of loach eyes prompted us to analyze the locomotor activities of eye-enucleated fish. As a result, they still showed nocturnal circadian activity. Thus, it is likely that extraocular photoreceptive tissue(s) also contribute to the photic input pathway, although loach eyes are a circadian photosensitive tissue. This suggests that the loach mainly uses not its vision but other stimuli, such as mechanical or chemical stimuli, detected by barbels, to coordinate its nocturnal behavior.

    DOI PubMed

  • A photoperiodic time measurement served by the biphasic expression of Cryptochrome1ab in the zebrafish eye.

    Keiko Okano, Yuya Saratani, Ayumi Tamasawa, Yosuke Shoji, Riko Toda, Toshiyuki Okano

    Scientific reports   10 ( 1 ) 5056 - 5056  2020.03  [International journal]

     View Summary

    The zebrafish (Danio rerio) is a model species that is used to study the circadian clock. It possesses light-entrainable circadian clocks in both central and peripheral tissues, and its core circadian factor cryptochromes (CRYs) have diverged significantly during evolution. In order to elucidate the functional diversity and involvement of CRYs in photoperiodic mechanisms, we investigated the daily expression profiles of six Cry transcripts in central (brain and eye) and peripheral (fin, skin and muscle) tissues. The zCry genes exhibited gene-specific diurnal conserved variations, and were divided into morning and evening groups. Notably, zCry1ab exhibited biphasic expression profiles in the eye, with peaks in the morning and evening. Comparing ocular zCry1ab expression in different photoperiods (18L:6D, 14L:10D, 10L:14D and 6L:18D) revealed that zCry1ab expression duration changed depending on the photoperiod: it increased at midnight and peaked before lights off. zCry1ab expression in constant light or dark after entrainment under long- or short-day conditions suggested that the evening clock and photic input pathway are involved in photoperiod-dependent zCry1ab expression. Laser microdissection followed by qRT-PCR analysis showed that the evening peak of zCry1ab was likely ascribed to visual photoreceptors. These results suggest the presence of an eye-specific photoperiodic time measurement served by zCry1ab.

    DOI PubMed

Awards 【 display / non-display

  • Zoological Science Award

    2021.06   The Zoological Society of Japan   Clock Gene Expression in the Eye Exhibits Circadian Oscillation and Light Responsiveness but is Not Necessary for Nocturnal Locomotor Activity of Japanese Loach, Misgurnus anguillicaudatus

    Winner: Yuya Saratani, Yuki Takeuchi, Keiko Okano, Toshiyuki Okano

Specific Research 【 display / non-display

  • 水産魚としての可能性を秘めたドジョウの行動制御機構に対する時間生物学的解析

    2020  

     View Summary

    ドジョウは日本、中国、韓国をはじめとする東アジアに広く分布する淡水魚である。これらの国々において、ドジョウは古くから食用魚として利用されてきた。ドジョウの養殖はいくつかの業者によって試みられているが、産業的に大きな成功には至っておらず、養殖方法の改良に不可欠な基本的生態の解明が待たれている。本研究ではドジョウの生態の中でも概日時計機構に着目し、時計遺伝子の発現変動と行動リズムを解析した。

  • 水産魚としての可能性を秘めたドジョウの行動制御機構に対する時間生物学的解析

    2020  

     View Summary

    ドジョウは日本、中国、韓国をはじめとする東アジアに広く分布する淡水魚である。これらの国々において、ドジョウは古くから食用魚として利用されてきた。ドジョウの養殖はいくつかの業者によって試みられているが、産業的に大きな成功には至っておらず、養殖方法の改良に不可欠な基本的生態の解明が待たれている。本研究ではドジョウの生態の中でも概日時計機構に着目し、時計遺伝子の発現変動と行動リズムを解析した。

  • 新たなモデル生物としての可能性を秘めたドジョウの生態解明に向けた研究

    2019  

     View Summary

    ドジョウは日本、中国、韓国をはじめとする東アジアに広く分布する淡水魚である。これらの国々において、ドジョウは古くから食用魚として利用されてきた。ドジョウの養殖はいくつかの業者によって試みられているが、産業的に大きな成功には至っておらず、養殖方法の改良に不可欠な基本的生態の解明が待たれている。生態の中でも個体の行動は特に基本的であり、本研究ではドジョウの行動を測定する形の確立に向けて実験を進めた。