Mechanisms of Purkinje cell migration

 描述（由申请人提供）：小脑协调和平衡，运动，情感和认知。小脑缺陷导致运动控制、平衡、姿势和学习障碍，是癫痫和自闭症的常见病理体征。小脑结构看似简单，实则发育复杂，两种主要细胞类型（浦肯野细胞和颗粒细胞）之间存在相互作用。 由此产生的细胞非自主效应一直是理解发育机制的障碍。教科书上的观点是浦肯野细胞通过沿着放射状胶质纤维的运动而迁移，并且缺乏环境因子Reelin抑制了从放射状胶质细胞的分离。然而，有理由质疑这一观点。首先，浦肯野细胞最近被认为是跨越而不是沿着放射状胶质细胞。第二，尽管Reelin调节前脑中的神经元迁移，但它调节的是不依赖于胶质细胞的迁移。此外，我们最近发现，E3泛素连接酶，CRL 5，调节浦肯野细胞迁移，但再次，细胞机制是未知的。这些问题目前很难解决，因为在正常环境中对单个浦肯野细胞进行遗传操作并观察其迁移是具有挑战性的。因此，我们的直接目标是调整方法来跟踪和遗传改变浦肯野细胞，因为它们在小脑中迁移和分化。然后，我们将结合联合收割机这些新方法与我们的经验，研究神经元迁移在新皮层，以解决浦肯野细胞迁移的关键问题，以及它们是如何调节的Reelin和CRL 5。拟议研究的一个附带好处是，我们开发的方法将是非常宝贵的产前和产后小脑发育，疾病和退化的未来调查。

 DESCRIPTION (provided by applicant): The cerebellum coordinates and synchronizes balance, movement, emotion and cognition. Cerebellar defects contribute to disorders in motor control, equilibrium, posture and learning and are frequent pathological signs in epilepsy and autism. The seeming simplicity of cerebellar structure belies its developmental complexity, with reciprocal interactions between the two principal cell types, the Purkinje cells and granule cells. The resulting cell non-autonomous effects have been an obstacle to understanding the developmental mechanisms. The textbook view has been that Purkinje cells migrate by locomotion along radial glia fibers, and absence of an environmental cue, Reelin, inhibits detachment from the radial glia. However, there are reasons to question this view. First, Purkinje cells were recently seen to move across rather than along radial glia. Second, even though Reelin regulates neuron migrations in the forebrain, it regulates glia-independent migration. In addition, we recently found that an E3 ubiquitin ligase, CRL5, regulates Purkinje cell migration, but, again, the cellular mechanism is unknown. These issues are currently difficult to address because it is challenging to genetically manipulate individual Purkinje cells and observe their migrations in a normal environment. Therefore, our immediate goal is to adapt methods to track and genetically alter Purkinje cells as they migrate and differentiate in the cerebellum. Then, we will combine these new methods with our experience studying neuron migration in the neocortex in order to address key questions of how Purkinje cells migrate and how they are regulated by Reelin and CRL5. An ancillary benefit of the proposed research is that the methods we develop will be invaluable for future investigation of pre- and post-natal cerebellar development, disease and degeneration.