Analysis of activity-dependent interactions between microglia and synapses

在我K99的第一年，我收到了一份offer，并接受了一个助理教授的职位。 马萨诸塞州大学医学院神经生物学系。因此，我申请 过渡到ROO阶段，在那里我将研究小胶质细胞特异性机制， 发育中大脑的突触重塑最终目标是将这些机制应用于 神经发育和神经精神障碍。 不成熟的突触形成了一个粗糙的接线图，必须在发育过程中重塑，以实现 成熟神经系统的精确连接特征。虽然很明显，神经活动驱动着 突触重塑，其潜在机制尚未完全了解。我们最近发现， 小胶质细胞通过以活性依赖性方式吞噬突触元件参与突触重塑。 然而，目前尚不清楚小胶质细胞是否吞噬完整的突触，或者这是否是一种非细胞自主的神经元。 活动此外，已知小胶质细胞改变其运动性和与突触的相互作用以响应 但这些反应的潜在分子机制和功能后果 是未知的。因此，本提案的目标是：1）艾米：测试小胶质细胞是 主动感知，相互作用，并吞噬完整的突触，以响应神经元的变化， 活动该实验室具有独特的优势，可以通过以下方式利用小胶质细胞成像方面的专业知识来解决这个问题： 2-光子活体成像，在K99阶段获得的技能。2)目的2：剖析分子 小胶质细胞对神经活动变化的反应机制。一些候选的小胶质细胞特异性 分子和细胞因子，包括IL-12。因此，活动依赖 将在以下基因缺陷的小鼠中评估小胶质细胞运动性和与突触的相互作用： 兴趣3)目的3：确定活性依赖性小胶质细胞反应的功能意义， 测试这些反应调节突触电路结构的发展的假设， 在先前鉴定和验证的基因缺陷的小鼠中发挥作用。

During the first year of my K99, I received an offer and accepted a positon as an Assistant Professor in the Neurobiology Department at the University of Massachusetts Medical School. As a result, I am applying for transition to the ROO phase where I will be investigating microglia-specific mechanisms driving activity-dependent synaptic remodeling in the developing brain. The ultimate goal is to apply these mechanisms to neurodevelopmental and neuropsychiatric disorders. Immature synapses form a crude wiring diagram that must remodel during development to achieve the precise connectivity characteristic of the mature nervous system. While It is clear that neural activity drives synaptic remodeling, the underlying mechanisms are not fully understood. We recently identified that microglia participate in synaptic remodeling by engulfing synaptic elements in an activity-dependent manner. However, it is unknown whether microglia engulf intact synapses or whether this is a non-cell autonomous event. In addition, it is known that microglia change their motility and interactions with synapse in response to neural activity but the underlying molecular mechanisms and functional consequences of these responses are unknown. As a result the goals of this proposal are to: 1) Aimi: Test the hypothesis that microglia are actively sensing, interacting with, and phagocytosing intact synapses in response to changes in neural activity. The laboratory is uniquely positioned to address this question with expertise in imaging microglia by 2-photon In vivo live Imaging, a skill acquired during the K99 phase. 2) Aim 2: Dissect the molecular mechanisms underlying microglia responses to changes in neural activity. A number of candidate microglia-specific molecules and cytokines have been identified and validated, including IL-12. Thus, activity-dependent microglia motility and interactions with synapses will be assessed In mice deficient in genes of interest. 3) Aim 3: Determine the functional significance of activity-dependent microglial responses by testing the hypothesis that these responses regulate the development of synaptic circuit structure and function in mice with deficiencies in genes previously identified and validated.