Regulation and regeneration of hippocampal plasticity by neural progenitor cells

 描述(申请人提供)：应聘者：应聘者为斯坦福大学3年级博士后，在Tony Wyss-Coray博士的实验室工作。这位候选人的直接目标是获得独立，并在一所专注于学术研究的大学或研究所建立自己的实验室，研究未分化的神经干细胞或祖细胞在海马体功能中的作用。她的长期目标是在一个学术研究中心建立一个在海马区可塑性和损伤反应方面的卓越实验室。她的目标是提高我们对海马体的理解，海马体是大脑记忆功能的重要区域，如何对环境做出积极或消极的反应，从而为人类大脑健康的治疗方法的发展提供信息。她还计划将高质量的年轻科学家指导作为她职业生涯的优先事项。环境：拟议的指导阶段研究将在斯坦福大学Tony Wyss-Coray博士的实验室进行。联合导师西奥·帕尔默博士和汤姆·兰多博士还将通过候选人和整个指导团队的季度个人会议和年度会议为候选人提供建议。斯坦福大学神经学系将每年举行强制性会议，候选人将向资深教师以及其他K99获奖者介绍她的研究和职业进展，并接受反馈和进一步的指导。斯坦福大学和冷泉港实验室的课程将提供实验室管理、拨款撰写和指导方面的正式指导。一个由几名顾问组成的团队还将帮助对候选人将在指导阶段学习的几个新程序进行技术培训，以及使用这些新程序进行研究设计。向独立的过渡已经确定了里程碑，并将得到主要导师和共同导师的切实支持，形式包括工作机会推荐、工作会谈练习和就业建议。主要导师将在以下方面投入大量精力 候选人实验室的建立通过：1)与神经科主任合作，确保候选人获得终身教职；2)在指导阶段就R01准备工作提供反馈；3)在国内和国际会议上宣传候选人的新实验室。研究：拟议的实验将研究未分化的神经干细胞和祖细胞(NSPC)在增强和损伤后在成人大脑中的新功能作用。在有益的自愿运动和伤害性的癫痫发作后，成年海马区内源性NSPC的增殖显著增加。以前的大多数研究都讨论了这些NSPC的分化产物导致的未成熟神经元的功能。这一建议将确定未分化的NSPC在癫痫发作和运动后通过分泌生长因子在海马区功能中的直接作用。这项研究的一个关键动机是为未来的治疗靶向提供信息 通过确定这一重要的、独特的细胞群如何改变成年海马区的损伤和可塑性反应，来研究NSPC。这项提议将为以前被认为是沉默的细胞年龄的成人神经发生带来功能上的影响。考虑到影响NSPC增殖的众多环境刺激，这些发现可能会对NSPC在海马可塑性中的作用产生广泛的影响。该项目的第一个目标将表征NSPC对生理和病理刺激的生长因子反应。来自急性解剖的成年小鼠海马区的荧光激活细胞分选技术将被用于分离癫痫发作或自愿车轮跑步运动后的NSPC。RNAseq将用于对比NSPC对病理刺激和生理刺激的转录反应。这些发现将代表一个丰富的数据集，将为未来许多关于NSPC如何参与调节海马体功能的研究奠定基础。为了确定NSPC分泌的生长因子的直接作用，这项建议将使用一种新的小鼠模型来诱导、NSPC特异性地敲除牙根生长因子，首先建立一个在NSPC中诱导敲除生长因子VEGF的模型。对于运动，NSPC中的一种生长因子(如血管内皮生长因子)的抑制将在成年后被诱导，然后暴露在一个未上锁的转轮中。随后，与运动相关的海马体功能增强的行为和免疫组织化学标记物将被量化，以确定NSPC中该生长因子的丢失是否会阻止运动的任何好处。对于癫痫发作，在生长因子基因敲除后，小鼠将全身或中枢暴露于红藻氨酸，以诱导不同程度的癫痫发作。行为和结构后遗症将被量化，以确定NSPC-生长因子的丢失对癫痫的恢复是有利还是不利。这些研究将阐明未分化神经前体细胞的功能，这是一个在很大程度上未被研究的细胞群体，但可能对设计治疗癫痫等对海马体产生不同影响的疾病具有重要意义。

 DESCRIPTION (provided by applicant): Candidate: The candidate is a 3rd year postdoctoral fellow at Stanford University in the lab of Dr. Tony Wyss- Coray. The candidate's immediate goals are to gain independence and establish her own lab at an academic research-focused university or institute studying the role of undifferentiated neural stem or progenitor cells in hippocampal function. Her long-term goals are to build a prominent lab in the area of hippocampal plasticity and injury response at an academic research center. She aims to improve our understanding of how the hippocampus, an essential brain area for memory function, responds to the environment, either positively or negatively and thereby inform development of therapeutics for human brain health. She also plans to make high quality mentoring of young scientists a priority in her career. Environment: The proposed Mentored Phase research will be conducted in the lab of Dr. Tony Wyss-Coray at Stanford University. Co-mentors Dr. Theo Palmer and Dr. Tom Rando will also advise the candidate through quarterly individual meetings and yearly meetings of the candidate and the entire mentoring team. The Stanford Neurology department will hold yearly mandatory meetings where the candidate will present her research and career progress to senior faculty, along with other K99 awardees, and receive feedback and further guidance. Coursework at Stanford and Cold Spring Harbor Lab will provide formal instruction in lab management, grant writing and mentoring. A team of several consultants is also in place to help with technical training on several new procedures that the candidate will learn in the Mentored Phase, as well as study design using these new procedures. The transition to independence has defined milestones and will be tangibly supported by the primary mentor and co-mentors in the form of job opportunity referrals, practice with job talks, and advice on offers. The primary mentor will invest significant effort in the establishment of the candidate's lab by: 1) working with the neurology department chair to secure a tenure-track position for the candidate, 2) providing feedback on R01 preparation during the Mentored Phase and 3) promoting the candidate's new lab at national and international conferences. Research: The proposed experiments will investigate a novel functional role for undifferentiated neural stem and progenitor cells (NSPCs) in the adult brain after enhancement and injury. The proliferation of endogenous NSPCs in the adult hippocampus increases dramatically after both beneficial voluntary exercise and injurious seizures. Most previous studies have debated the function of the immature neurons that result from the differentiated products of these NSPCs. This proposal will determine the direct role of undifferentiated NSPCs in hippocampal function via secretion of growth factors after both seizures and exercise. A key motivation for this research is to inform future therapeutic targeting of NSPCs by determining how this important, unique cell population alters injury and plasticity responses in the adult hippocampus. This proposal will introduce functional implications for adult neurogenesis at a cellular age previously thought to be silent. Given the numerous environmental stimuli that impact NSPC proliferation, these findings could have wide-reaching implications for the role of NSPCs in hippocampal plasticity. The first aim of this project will characterize the growth factor response of NSPCs to physiological and pathological stimuli. Fluorescence-activated cell sorting techniques from acutely dissected murine adult hippocampus will be employed to isolate NSPCs after seizures or voluntary wheel running exercise. RNAseq will be used to contrast the profiles of NSPC transcriptional responses to pathological vs physiological stimuli. These findings will represent a rich dataset that will infor many future investigations of how NSPCs participate in regulating hippocampal function. To determine the direct role of NSPC-secreted growth factors, this proposal will use a novel mouse model for inducible, NSPC-specific knockdown of floxed growth factors, starting with an established model for inducible knockdown of the growth factor VEGF in NSPCs. For exercise, knockdown of a growth factor (like VEGF) in NSPCs will be induced in adulthood, followed by exposure to an unlocked running wheel. Behavioral and immunohistochemical markers of exercise-related enhancement of hippocampal function will then be quantified to determine whether loss of that growth factor from NSPCs prevents any benefits of exercise. For seizures, after growth factor knockdown, mice will be exposed to kainic acid either systemically or centrally to induce different levels of seizure severity. Behavioral and structural sequela will thn be quantified to determine whether loss of NSPC-growth factor is beneficial or detrimental to recovery from seizure. These studies will shed light on the function of undifferentiated neural progenitors, a largely uninvestigated cell population but one that may have important implications for design of therapies for disorders that differentially impact the hippocampus such as epilepsy.