Development of cell manipulation technology using photothermal conversion

2022 Fiscal Year Final Research Report

• Project Area: Next-generation non-invasive biological deep-tissue manipulation by biomolecular engineering and low physical energy logistics
• Project/Area Number: 20H05757
• Research Category: Grant-in-Aid for Transformative Research Areas (B)
• Allocation Type: Single-year Grants
• Review Section: Transformative Research Areas, Section (III)
• Research Institution: Kyoto University
• Principal Investigator: Imamura Hiromi 京都大学, 生命科学研究科, 准教授 (20422545)
• Project Period (FY): 2020-10-02 – 2023-03-31
• Keywords: 色素タンパク質 / 光熱変換 / レーザー / カルシウム / TRPチャネル

Outline of Final Research Achievements

We have developed a technique to induce the opening of temperature-sensitive channels by heat generated by laser irradiation of dye proteins. First, the feasibility of using the dye protein ShadowR as a nano-sized molecular heater was confirmed using Sirius, a temperature-sensitive blue fluorescent protein. Next, ShadowR was inserted into the temperature-sensitive channel TRPV4. When the fusion protein was expressed in cultured cells and irradiated with a laser pulse at a wavelength absorbed by ShadowR, calcium ion influx was observed through the opening of the TRPV4 channel. On the other hand, the influx of calcium ions did not stop even after the laser irradiation was stopped, indicating that the control of calcium ion influx by photothermal conversion remains an issue.

Free Research Field

生物物理学、細胞生物学

Academic Significance and Societal Importance of the Research Achievements

近年、光によって細胞機能を操作する「光遺伝学（オプトジェネティクス）」という手法が盛んに開発され、基礎研究分野で利用されている。従来の光遺伝学では光によって機能が変わるタンパク質を利用する。今回の研究では、色素タンパク質の光熱変換によって光を局所的な熱に変換し、その熱を熱感受性タンパク質に伝えることで細胞機能を制御できることを示した。このような細胞操作技術は従来にないものであり、色素タンパク質と熱感受性タンパク質の組み合わせを変えることで多様な細胞制御が可能になるかもしれない。