Neurogenic plasticity and brain development

大脑中新神经元的产生，这一称为神经发生的过程，贯穿一生。这是因为存在少量干细胞群体，这些干细胞持续存在于大脑的特定区域(称为干细胞壁龛)，这些干细胞经历细胞分裂，产生新的神经元，在功能上整合到现有的神经回路中。过去20年的研究表明，成熟大脑中的神经发生不是一个被动的过程，而是可以根据干细胞分裂的速度、产生的新神经元的类型或新神经元存活的程度进行修改。这种结构可塑性，在这里被称为神经源性可塑性，被认为依赖于大脑与动物环境相互作用的内在机制。然而，我们对这种互动的了解相当有限，这代表了该领域的一个强烈兴趣的话题。我们的研究调查动物的外部环境如何影响大脑中的神经发生，以及这是否会影响行为。*我们由NSERC资助的研究的长期目标是使用斑马鱼来获得对环境诱导的大脑神经性可塑性的分子和细胞基础的新见解。为了实现这一目标，我们制定了一项研究提案，将解决三个实验目标。首先，我们将探索改变视觉线索如何改变大脑中不同干细胞缝隙中的神经发生。通过利用基因方法，我们可以追踪新神经元的诞生时间，它们来自大脑的哪个部分，并确定它们成为的神经元类型。我们将在标准环境条件和视觉变化的环境下进行这些实验，以确定感觉输入如何影响神经发生。其次，我们将研究感觉环境的变化对行为的影响，以及神经发生本身是否对这些影响是必要的。一个数字跟踪系统将被用来观察当动物经历视觉环境改变时，依赖视觉的运动是否会受到影响，遗传方法将被用来专门阻止神经发生，看看这是否对行为有同样的影响。最后，利用遗传和基因组技术，我们将调查不同的分子信号通路在多大程度上作为机械链接，改变神经发生输出，以响应不断变化的视觉环境。*我们的研究将阐明经验诱导的神经源性可塑性的机制，以更深入地理解环境、大脑结构和行为之间的基本关系。除了发展神经科学，我们的工作将对其他领域的研究具有广泛的影响，重点是动物与环境的相互作用，如行为生态学、认知神经科学以及神经修复和康复。

The production of new neurons in the brain, a process called neurogenesis, continues throughout life. This is made possible by the existence of small populations of stem cells that persist in defined regions of the brain (called stem cell niches) that undergo cell division to produce new neurons functionally integrating into existing neural circuits. Research over the last 20 years has shown that neurogenesis in the mature brain is not a passive process, but instead can be modified with respect to the rate of stem cell division, the type of new neurons produced, or the extent to which new neurons survive. This form of structural plasticity, referred to here as neurogenic plasticity,' is thought to depend on mechanisms that are intrinsic to the brain interacting with the animal's environment. However, our understanding of this interaction is quite limited and this represents a topic of intense interest in the field. Our research investigates how an animal's external environment influences neurogenesis in the brain and whether this affects behaviour.***The long-term objective of our NSERC-funded research is to use zebrafish to gain novel insight into the molecular and cellular basis of environment-induced neurogenic plasticity in the brain. To accomplish this objective, we have developed a research proposal that will address three experimental aims. First, we will explore how altering visual cues can modify neurogenesis in distinct stem cell niches in the brain. By utilizing genetic methods, we can trace when new neurons are born, what part of the brain they originate from, and identify the type of neuron they become. We will perform these experiments under standard environmental conditions as well as visually altered environments to determine how sensory input affects neurogenesis. Second, we will examine the impact that a change in sensory environment has on behaviour and whether neurogenesis itself is necessary for these effects. A digital tracking system will be used to see if vision-dependent movement is affected as animals experience an altered visual environment, and genetic methods will be used to specifically block neurogenesis to see if this has the same effect on behaviour. Finally, using both genetic and genomic technologies, we will investigate the extent to which different molecular signalling pathways serve as mechanistic links that modify neurogenesis output in response to a changing visual environment.***Our research will elucidate mechanisms of experience induced neurogenic plasticity for a deeper understanding of the fundamental relationship between the environment, brain structure, and behaviour. Beyond developmental neuroscience, our work will have broad implications for other fields of research with a focus on animal-environment interactions, such as behavioural ecology, cognitive neuroscience, and neural repair and rehabilitation.**