酒亞明組發現非典型肌球蛋白調控微絲應力纖維融合蛋白

　　肌球蛋白myosin與微絲actin形成具有收縮性的肌動肌球蛋白束，在肌肉細胞中以肌小節形式存在，在非肌肉細胞中以微絲應力纖維形式存在，是細胞定向運動的動力結構，特別對癌細胞的轉移、免疫細胞的靶向運動等生命過程至關重要，但其組裝的分子機制和動態過程研究較少。

Myosin-18B基因突變造成新生兒肌無力的病例 (Malfatti et al., 2015)

　　2018年12月20日，Current Biology在線發表了中國科學院上海巴斯德研究所酒亞明研究組的研究論文Myosin-18B promotes the assembly of myosin II stacks for maturation of contractile actomyosin bundles 。該研究首次識別出新的促進肌動肌球蛋白束（actomyosin bundles）融合的蛋白分子，為癌細胞實現轉移提供了細胞動力學證據。

　　該研究通過基于生物素biotin的蛋白質組學篩選，鑒別出一系列與肌動肌球蛋白束組裝和動力學調節相關的基因。借助多種前沿成像技術，包括活細胞成像、結構光照明超高分辨顯微成像、生物機械力成像等，首次在活體細胞水平下紀錄到納米級別分辨率的微絲應力纖維融合的動態生理過程，并深入研究了非典型的馬達蛋白myosin-18B作為“膠水”分子，促進肌動肌球蛋白融合成具有收縮性的蛋白束的分子機制。該研究揭示了細胞實現運動的分子結構基礎和動態重組過程，為調控癌細胞或免疫細胞的轉移提供了潛在的治療靶點。

　　據悉，該研究得到赫爾辛基大學Pekka Lappalainen教授的大力支持。酒亞明研究員為本文第一作者和共同通訊作者。

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