Identification and functional analysis of molecules that regulate intracellular temperature

2022 Fiscal Year Final Research Report

• Project/Area Number: 20K21388
• Research Category: Grant-in-Aid for Challenging Research (Exploratory)
• Allocation Type: Multi-year Fund
• Review Section: Medium-sized Section 43:Biology at molecular to cellular levels, and related fields
• Research Institution: Doshisha University (2022); Kyoto University (2020)
• Principal Investigator: Umeda Masato 同志社大学, 研究開発推進機構, 嘱託研究員 (10185069)
• Project Period (FY): 2020-07-30 – 2023-03-31
• Keywords: 細胞内温度 / 脂肪酸不飽和化酵素 / 膜脂質 / ミトコンドリア / ショウジョウバエ / 酸化的リン酸化 / ATP合成酵素

Outline of Final Research Achievements

Intracellular temperature affects a wide range of cellular functions in living organisms. However, it remains unclear whether temperature in individual animal cells is controlled autonomously as response in fluctuations in environmental temperature. We find that the intracellular temperature of steady-state Drosophila S2 cells is maintained in a manner dependent on delta9-fatty acid desaturase DESAT1.The DESAT1-mediated increase of intracellular temperature is caused by the enhancement of F1Fo-ATPase-dependent mitochondrial respiration that is coupled with thermogenesis. We also reveal that F1Fo-ATPase-dependent mitochondrial respiration is potentiated by cold exposure through the remodeling of mitochondrial cristae structure via DESAT1-dependent unsaturation of mitochondrial phospholipid acyl chains. Based on these findings, we propose a cell-autonomous mechanism for intracellular temperature control during environmental temperature changes.

Free Research Field

生化学

Academic Significance and Societal Importance of the Research Achievements

温度は、分子の存在状態や反応性を規定する最も重要な物理量であり、生化学反応を始めとする全ての生命活動が温度により強く影響を受ける。従来、単培養した数十マイクロメーター程の細胞内温度は、早い熱拡散により細胞外溶液と熱平衡状態に達し、個々の細胞が自律的に細胞内温度の恒常性維持を図っているとは考えられて来なかった。本研究により、環境温の変動に対応して細胞内温度を制御する新たな分子機構が明らかにされ、「細胞内微小空間における細胞自律的な温度制御」と言う新たな概念を提出する点にその学術的意義がある。