Research and Utilization Division, SPring-8, Japan Synchrotron Radiation Research Institute (JASRI), Sayo-gun, Hyogo, Japan.
Science. 2013 Sep 13;341(6151):1243-6. doi: 10.1126/science.1237266. Epub 2013 Aug 22.
The high-frequency wing beat of higher-order insects is driven by self-sustained oscillations of constantly activated flight muscles. However, whether its underlying mechanism is based on flight muscle-specific features or on preexisting contractile functions is unknown. Here, we recorded X-ray diffraction movies, at a rate of 5000 frames/second, simultaneously from the two antagonistic flight muscles of bumblebees during wing beat. Signals that occurred at the right timing for triggering each wing-beat stroke were resolved in both muscles. The signals likely reflect stretch-induced myosin deformation, which would also enhance force in vertebrate muscles. The results suggest that insects use a refined preexisting force-enhancing mechanism for high-frequency wing beat, rather than developing a novel mechanism.
高等昆虫的高频拍动翅膀由不断激活的飞行肌肉的自维持振荡驱动。然而，其潜在机制是基于飞行肌肉的特有特征，还是基于预先存在的收缩功能尚不清楚。在这里，我们以每秒 5000 帧的速度同时记录了大黄蜂的两个拮抗飞行肌肉在拍动翅膀时的 X 射线衍射电影。在两个肌肉中都解析出了在触发每个翅膀挥动时出现的信号。这些信号可能反映了伸展诱导的肌球蛋白变形，这也会增强脊椎动物肌肉的力量。结果表明，昆虫利用一种精细的预先存在的力增强机制来进行高频拍动翅膀，而不是开发一种新的机制。
