Collaborative Research: Molecular Determinants of Power Inputs and Outputs of Synchronous Flight Muscle in Vivo

项目标题：合作研究：活体同步飞行肌肉功率输入和输出的分子决定因素主要研究人员：欧文、托马斯·C和托马斯·L·丹尼尔国家科学基金会项目编号：IOS 1022058和1022471所有移动的动物，从人类到飞行昆虫，都与肌肉一起运作，这些肌肉不仅周期性地产生力，而且还产生显著的热量。本研究项目旨在了解肌肉中温度依赖力产生的分子基础和生理后果。与许多其他生物速率过程一样，肌肉的速度和功率输出受到温度的强烈影响。令人惊讶的是，为鹰蛾飞行提供动力的肌肉产生的热量显示出很大的温度梯度，与更深、更绝缘的肌肉相比，更多的浅层肌肉在更低的温度下工作。这种温度梯度具有深远的功能后果，很可能是许多移动生物的普遍结果。研究人员将检验温度梯度导致功能梯度的概念。因此，更深、更热、更肌肉的亚单位可以作为推动运动的发电机，而更冷的亚单位可以作为弹性能量存储系统。所有这些功能都与蛋白质马达一起运作，这些马达将从分子水平到运动动物的完全完整的肌肉进行检查。为了解决这一问题，将混合使用高速X射线成像方法和整体肌肉力量和能量测量方法。人类和其他动物的肌肉体积产生的热量，加上散热的过程，表明温度梯度可能比历史上假设的更常见。因此，肌肉的温度依赖功能在单个肌群内可能会在空间上发生变化，这可能是一个普遍现象。此外，六头巨嘴鱼的飞行肌肉将为了解动物的肌肉功能提供一个新的模型系统。这一项目的结果将是发展和改进X射线衍射法来探测活体肌肉功能。

Project Title: Collaborative Research: Molecular Determinants of Power Inputs and Outputs of Synchronous Flight Muscle In Vivo Principal Investigators: Irving, Thomas C, and Thomas L. Daniel NSF Project Numbers: IOS 1022058 and 1022471 All moving animals, from humans to flying insects, operate with muscles that not only cyclically generate force, they do so while generating significant heat. This research project is aimed at understanding the molecular basis and physiological consequences of temperature dependent force generation in muscle. As with many other biological rate processes, the speed and power output of muscle is strongly influenced by temperature. Surprisingly, heat generation by the muscles that power flight in Hawkmoths show a large temperature gradient, with more superficial muscles operating at cooler temperatures than deeper, more insulated, muscles. This temperature gradient has profound functional consequences and is likely a general result for many moving creatures. The researchers will examine the notion that thermal gradients lead to functional gradients. Thus, deeper warmer, muscle subunits may serve as power generators driving locomotion whereas cooler subunits may act as elastic energy storage systems. All of this function operates with protein motors that will be examined from the molecular level to the fully intact muscle in a moving animal. A mix of high-speed x-ray imaging methods and whole muscle force and energy measurement methods will be used to tackle this problem. The combination of heat generation by the volume of muscle in humans and other animals, combined with processes that dissipate heat suggests that temperature gradients may be more common than historically assumed. Thus it is likely a general phenomenon that the temperature dependent function of muscle will vary spatially within a single muscle group. In addition, the flight muscle of Manduca sexta will provide a new model system for understanding muscle function in animals in general. A result of this project will be development and refinement of x-ray diffraction methods to probing muscle function in vivo.