Challenge toward development an artificial tool for cellular liquid-liquid phase separation by using optical condensation

2023 Fiscal Year Final Research Report

• Project/Area Number: 22K20512
• Research Category: Grant-in-Aid for Research Activity Start-up
• Allocation Type: Multi-year Fund
• Review Section: 0403:Biomedical engineering and related fields
• Research Institution: Osaka Metropolitan University
• Principal Investigator: Toyouchi Shuichi 大阪公立大学, 研究推進機構, 特任講師 (40851382)
• Project Period (FY): 2022-08-31 – 2024-03-31
• Keywords: 光捕捉 / 光濃縮 / 液液相分離

Outline of Final Research Achievements

We demonstrated laser-induced liquid-liquid phase separation (LLPS) of a protein by focusing a laser at the air-solution interface. When a laser is focused on the air-solution interface of a protein solution, a transient and local highly concentrated domain can be formed near the focus point. We conducted basic research to develop a new tool to artificially induce intracellular LLPS by utilizing spatiotemporally controlled optical condensation. Using Hen egg white lysozyme (HEWL) as a model protein, we verified that LLPS could be induced in HEWL solution by optical condensation and succeeded in forming LLPS microdroplets. It has also been shown that when a mixed solution of HEWL and bovine serum albumin underwent optical condensation to mimic the intracellular molecular crowding environment, the optical condensation-induced LLPS microdroplet was formed more efficiently than a single protein solution.

Free Research Field

物理化学

Academic Significance and Societal Importance of the Research Achievements

細胞内液液相分離(LLPS)によって形成される非膜オルガネラが様々な生体現象に関わっていることが示され大きな注目を集めている。一方で、LLPSを高い時空間分解能で確実に捉える人工LLPSツールが求められている。本研究で得られた成果は、光濃縮を高時空分解能を有する人工LLPSツールとして利用可能である事を示し、光濃縮誘起LLPSを通した生化学反応制御さらには細胞操作を可能とする新規光技術へ発展する事が期待できる。観測された光濃縮誘起LLPSは、光濃縮下に特異的なLLPSである事が示唆されており、光濃縮下での生体分子間相互作用の制御に繋がる新しい知見として、今後の研究発展が大いに期待できる。