Molecular mechanisms for redox homeostasis studied by Chlamydomonas phototaxis

2018 Fiscal Year Final Research Report

• Project/Area Number: 16K14752
• Research Category: Grant-in-Aid for Challenging Exploratory Research
• Allocation Type: Multi-year Fund
• Research Field: Plant molecular biology/Plant physiology
• Research Institution: Tokyo Institute of Technology
• Principal Investigator: Wakabayashi Ken-ichi 東京工業大学, 科学技術創成研究院, 准教授 (80420248)
• Research Collaborator: Hisabori Toru ; Yoshida Keisuke ; Ueki Noriko
• Project Period (FY): 2016-04-01 – 2019-03-31
• Keywords: 走光性 / レドックス / 鞭毛・繊毛 / 緑藻

Outline of Final Research Achievements

Redox homeostasis maintains the cellular redox (reduction-oxidation) balance moderately reduced. However, changes in respiratory and photosynthetic activities can lead to oxidized- or excessively reduced state. We succeeded in the isolation of a mutant in which the relationship between phototaxis and intracellular redox state is disrupted in the green alga Chlamydomonas; normally, oxidized cells shows positive phototaxis and reduced cells show negative phototaxis. Those mutants show positive phototaxis even when they are reduced. These strains had an abnormality in which photosynthetic activity decreased. Unfortunately, we were not able to identify the causative gene during this period, but we were able to find an interesting phenomenon in which events occurring in chloroplasts define the direction of cell movement. In the future, the ministry will expedite efforts to identify the genes responsible for the disease.

Free Research Field

細胞運動生理学

Academic Significance and Societal Importance of the Research Achievements

学術的には、葉緑体チラコイド膜で起きている現象（還元力伝達の遅滞）が、細胞全体が示す運動方向の異常につながるという新奇現象を見出したことが大きな意義である。この分子メカニズムを明らかにすることができれば、野外における有用藻類培養の効率化や、有害藻類の駆除などに応用できる可能性がある。