肌球蛋白myosin与微丝actin形成具有收缩性的肌动肌球蛋白束，在肌肉细胞中以肌小节形式存在，在非肌肉细胞中以微丝应力纤维形式存在，是细胞定向运动的动力结构，特别对癌细胞的转移、免疫细胞的靶向运动等生命过程至关重要，但其组装的分子机制和动态过程研究较少。
Myosin-18B基因突变造成新生儿肌无力的病例 (Malfatti et al., 2015)
2018年12月20日，Current Biology在线发表了中国科学院上海巴斯德研究所酒亚明研究组的研究论文Myosin-18B promotes the assembly of myosin II stacks for maturation of contractile actomyosin bundles 。该研究首次识别出新的促进肌动肌球蛋白束（actomyosin bundles）融合的蛋白分子，为癌细胞实现转移提供了细胞动力学证据。
该研究通过基于生物素biotin的蛋白质组学筛选，鉴别出一系列与肌动肌球蛋白束组装和动力学调节相关的基因。借助多种前沿成像技术，包括活细胞成像、结构光照明超高分辨显微成像、生物机械力成像等，首次在活体细胞水平下纪录到纳米级别分辨率的微丝应力纤维融合的动态生理过程，并深入研究了非典型的马达蛋白myosin-18B作为“胶水”分子，促进肌动肌球蛋白融合成具有收缩性的蛋白束的分子机制。该研究揭示了细胞实现运动的分子结构基础和动态重组过程，为调控癌细胞或免疫细胞的转移提供了潜在的治疗靶点。
据悉，该研究得到赫尔辛基大学Pekka Lappalainen教授的大力支持。酒亚明研究员为本文第一作者和共同通讯作者。
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