The mechanical control of mechanosensation

机械感觉的机械控制

• 批准号: 8934211
• 负责人: Michael Krieg
• 金额: $ 8.92万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2014
• 资助国家: 美国
• 起止时间: 2014-09-30 至 2016-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8934211
• 关键词: Actins; Animal Model; Animals; Arteries; Baroreflex; Behavior; Behavioral; Binding; Biochemical; Biochemistry; Biological Assay; Biology; Breathing; C-terminal; Caenorhabditis elegans; Calcium; Cardiovascular Diseases; Cells; Code; Communities; Cues; Cytoskeletal Proteins; Cytoskeleton; Data; Detection; Development; Devices; Disease; Embryo; Engineering; Erythrocytes; Failure; Fluorescence Resonance Energy Transfer; Genetic Models; Genetic Screening; Goals; Health; Hearing; Heart; Heart failure; Homologous Gene; Hypertension; Image; In Vitro; Individual; Ion Channel; Ion Transport; Knowledge; Lead; Life; Light; Link; Locomotion; Love; Lung; Lung diseases; Mammals; Measures; Mechanical Stimulation; Mechanical Stress; Mechanics; Mentors; Methods; Microfluidics; Molecular; Monitor; Motor Neurons; Movement; Mutate; Neuraxis; Neurons; Neurosciences; Pathway interactions; Pattern; Peptides; Peripheral; Phase; Phenotype; Physics; Physiological; Physiology; Play; Positioning Attribute; Posture; Pressoreceptors; Property; Proprioception; Proprioceptor; Protein Binding; Proteins; Reporter; Research; Resolution; Role; Sensory; Shapes; Signal Transduction; Spectrin; Stimulus; Stress; Stretch Receptors; Stretching; Subconscious; System; Tail; Techniques; Technology; Testing; Time; Touch sensation; Transgenic Animals; Transgenic Organisms; Vascular System; Walking; design; falls; in vivo; link protein; molecular mechanics; mutant; novel; overexpression; receptor; research study; response; sensor; somatosensory; sound; tool; transmission process

 DESCRIPTION (provided by applicant): Mechanical force plays pivotal roles in the responses to touch, sound and light, but also to stresses generated in our own body. Specialized sensory cells in our vascular system are periodically deformed with every beat of our heart, yet remain sensitive enough to monitor the mechanical state of our body. Disruption of the sensory capacity of these baroreceptors in our arteries and stretch receptive proprioceptors in our lungs can lead to cardiovascular and pulmonary diseases. Despite this importance to our physiology, the factors contributing to the sense of mechanical force remain elusive due to challenges in studying their consequences on individual cells. Whereas the technology to measure and exert forces on single cells is becoming available, the tools to detect such deformations inside living cells do not yet exist. To investigate the basic mechanotransduction pathways in neurons, this proposal integrates physics, biology, and engineering within the context of the genetic model organism, C. elegans. Of the 302 neurons in C. elegans, 60 are activated by mechanical force. Touch receptor neurons, in particular, are extremely well characterized in terms of their known physiological responses and molecular machinery, and are thus a powerful system to study the cellular response to mechanical stress. Moreover, C. elegans neurons are subjected to cyclic deformation as the animal moves due to the sinusoidal locomotion pattern, analogous to proprioceptive mechanosensors in our own bodies. Importantly, many components of mechano-electrical transduction (MeT) are conserved in mammals. The mentored phase of this project will identify the biochemical force transmission pathway during touch and proprioception that leads to the opening of the MeT channel MEC-2, a conserved protein pivotal to the response to mechanical force in mammals. Aim 1 will utilize a fluorescent force reporter assay in conjunction with the design and implementation of a novel device to visualize mechanical force effects on MEC-2 in live worms, and Aim 2 will define the interaction of MEC-2 with components of the cellular cytoskeleton using classical biochemistry and genetic screens. These results will show, for the first time, how force gates a eukaryotic MeT channel, relevant to a wide research community in somatosensory neuroscience and hearing. In the long-term, independent phase (Aim 3), this project will aim to understand how mechanical properties of molecules and cells influence decisions of a freely behaving animal and resolve the mechanism of mechanosensation on the molecular, cellular, and systems level. This will involve the characterization of stretch-receptive proprioceptors in C. elegans by calcium imaging of neuron activation, targeted stimulation of isolated proprioceptor culture on elastic substrates and locomotive behavior of transgenic worms carrying modified cytoskeletal proteins. These experiments will be the first that link molecular mechanics to specific behavioral phenotypes such as touch and locomotion.

 描述（由申请人提供）：机械力在对触摸、声音和光的反应中起着关键作用，而且对我们自己身体产生的压力也起着关键作用。我们血管系统中专门的感觉细胞随着我们心脏的每一次跳动而周期性地变形，但仍然保持足够的敏感性来监测我们身体的机械状态。我们动脉中的压力感受器和肺部的拉伸感受本体感受器的感觉能力的中断可能导致心血管和肺部疾病。 尽管这对我们的生理学很重要，但由于研究它们对单个细胞的影响的挑战，导致机械力感的因素仍然难以捉摸。虽然测量和施加力于单细胞的技术正在变得可用，但检测活细胞内这种变形的工具还不存在。 为了研究神经元中的基本机械传导通路，本研究将物理学、生物学和工程学结合在遗传模式生物C。优雅的在C. elegans，60是由机械力激活的。特别是触觉感受器神经元，在其已知的生理反应和分子机制方面具有非常好的特征，因此是研究细胞对机械应力反应的强大系统。此外，C.由于正弦运动模式，当动物移动时，秀丽线虫神经元经历周期性变形，类似于我们自己身体中的本体感受机械传感器。重要的是，机械-电转导（MeT）的许多组分在哺乳动物中是保守的。 该项目的指导阶段将确定触摸和本体感受过程中的生化力传递途径，该途径导致MeT通道MEC-2的开放，MEC-2是一种保守的蛋白质，对哺乳动物的机械力反应至关重要。目标1将利用荧光力报告基因测定结合设计和实施一种新的设备，以可视化机械力对活蠕虫中MEC-2的影响，目标2将使用经典的生物化学和遗传筛选来定义MEC-2与细胞细胞骨架组分的相互作用。这些结果将首次显示，如何强制门一个真核MeT通道，相关的体感神经科学和听力广泛的研究社区。 在长期的独立阶段（目标3），该项目的目标是了解分子和细胞的机械特性如何影响自由行为动物的决定，并在分子，细胞和系统水平上解决机械感觉的机制。这将涉及C. elegans通过神经元激活的钙成像，在弹性基质上分离的本体感受器培养物的靶向刺激和携带修饰的细胞骨架蛋白的转基因蠕虫的运动行为。这些实验将是第一个将分子力学与特定行为表型（如触摸和运动）联系起来的实验。