RUI: Adult Compensatory Plasticity in an Invertebrate Sensory System

非技术段落：神经科学中最重要的问题之一是神经系统在衰老过程中如何保持灵活性。在年轻的生物体中，神经系统是高度可塑性的；神经细胞可以改变它们的形状和功能。较老的神经系统往往不太灵活，大规模重组是不寻常的。这项研究考察了成年蟋蟀负责听力的神经回路的可塑性，这种回路可以在受损后再生和重新连接听觉神经连接。这种可塑性导致听力损失的功能恢复，这在不同的蟋蟀之间是不同的。这个项目的目标是了解支配这种可塑性的机制，并解释个体之间功能恢复的差异性。因为这些相同或相似的机制存在于各种各样的生物体中，所以从这些板球实验中学到的东西将普遍适用于其他生物体的电路。这项工作的更广泛的科学影响将是它有助于更深入地了解成人神经系统可塑性的机制，以及如何利用这些知识来促进神经系统创伤后的功能恢复。这项工作还将对鲍登学院和缅因州的教育产生重要影响。本科生将积极参与拟议的科学研究，并将特别努力从代表不足的群体中发现、支持和留住学生。此外，PI和她的学生将在当地小学和Wabanaki中学参加一年一度的STEM外展活动，扩大该基金的社会影响。技术段落：关于神经系统的一个长期问题是，它们在成熟时如何保持可塑性。这项研究项目关注的是成年期罕见的大规模解剖可塑性的例子之一。板栗的成体听觉系统在失去一只耳朵后表现出深刻的结构可塑性，包括树突和轴突的大规模生长和分支。这些变化导致特定波长的生理恢复，以补偿耳朵的损失；不同蟋蟀的恢复程度差异很大。PI和她的学生将检验这样一个假设，即解剖发芽的程度与恢复有关，这体现在对听觉刺激和听觉系统恢复的行为指标的生理反应的强度上。单个动物体内的恢复程度将通过测试负趋音性、听觉神经元对声音的电生理反应以及量化听觉神经元的树突和轴突变化来评估。将使用贝叶斯统计建模来分析这些级别的数据。实验将测试是否有可能通过改变信号素信号来操纵形式和功能。DsRNA将被用来操纵SEMA和丛水平，并将评估任何由此导致的形态、生理和行为功能的变化。鉴于神经元发育和可塑性策略的进化守恒，从使用G.bimaculatus的这些实验中学到的将适用于各种其他组织中的去传入电路。该奖项反映了NSF的法定使命，并通过使用基金会的智力优势和更广泛的影响审查标准进行评估，被认为值得支持。

Non-Technical Paragraph:One of the most important questions in neuroscience is how flexible nervous systems remain as they age. In young organisms, nervous systems are highly plastic; neural cells can change their shape and their function. Older nervous systems tend to be less flexible, and large-scale reorganizations are unusual. This research examines adult plasticity in neural circuits responsible for hearing in crickets, which can regrow and rewire auditory neural connections after damage. This plasticity produces functional recovery of hearing loss that is variable among individual crickets. The goal of this project is to understand the mechanisms that govern this type of plasticity, and to explain the variability in functional recovery among individuals. Because these same or similar mechanisms exist in a wide variety of organisms, what is learned from these cricket experiments will be generally applicable to circuits in other organisms. The broader scientific impact of the work will be its contribution to a deeper understanding of the mechanisms of adult nervous system plasticity and how this knowledge can be used to promote functional recovery after nervous system trauma. This work will also have important educational impacts both at Bowdoin College and within Maine. Undergraduates will be active participants in the proposed scientific research, and a special effort will be made to identify, support, and retain students from underrepresented groups. In addition, the PI and her students will participate in annual STEM outreach activities at local elementary schools and with Wabanaki middle school students, widening the societal impact of the funding.Technical Paragraph:A persistent question about nervous systems is how plastic they remain as they mature. This research project focuses on one of the rare examples of large-scale anatomical plasticity seen in adulthood. The adult auditory system of the cricket Gryllus bimaculatus demonstrates profound structural plasticity after the loss of an ear, consisting of large-scale growth and branching of dendrites and axons. These changes result in wavelength-specific physiological recovery that compensates for the loss of the ear; the extent of recovery in different crickets is highly variable. The PI and her students will test the hypothesis that the extent of anatomical sprouting correlates with recovery, as seen in the strength of physiological responses to auditory stimuli and to behavioral indications of auditory system recovery. The extent of recovery within individual animals will be assessed by testing negative phonotaxis, electrophysiological responses of auditory neurons to sound, and quantifying dendritic and axonal changes in auditory neurons. Bayesian statistical modeling will be used to analyze the data across these levels. Experiments will test whether it is possible to manipulate form and function by altering semaphorin signaling. DsRNA will be used to manipulate sema and plex levels, and any resulting changes in morphology, physiology and behavioral function will be assessed. Given the evolutionary conservation of neuronal strategies for development and plasticity, what is learned from these experiments using G. bimaculatus will be applicable to deafferented circuits in a wide variety of other organisms.This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.