Mapping glycan-dependent neurexin interactomes

项目摘要 Neurexin是突触前神经元上重要的细胞粘附分子，介导重要的结合事件 形成突触，神经元通讯的最基本单位。neurexin结构的改变 是许多认知和神经疾病的基础。我们对neurexin结构的有限了解阻碍了我们对neurexin结构的研究。 开发靶向治疗以缓解这些疾病的能力。最近的发现发现neurexin是 一种由多种糖胺聚糖结构修饰的糖缀合物。这些发现令人振奋， 需要对neurexin结构结合进行全面和聚糖依赖性理解 关系。然而，鉴于这些研究的多样性和异质性， 糖胺聚糖使用植根于化学生物学的创新蛋白聚糖编辑平台，我们将 制造确定的和充满的neurexin胞外域并改进与已知结合配偶体的结合关系 （评价阶段，目标1）。随后，我们将把这些分子应用到活的原代神经元上，并进行展示 在细胞表面上以从头开始的方式，这样我们就可以使用邻近标记来捕获它们相应的 相互作用组（发现阶段，目标2）。这些复杂的材料将作为重要的工具， 评估neurexin配体，本申请的总体结果将是neurexin的目录 由其糖基化状态定义的相互作用体。

PROJECT SUMMARY Neurexin is an important cell adhesion molecule on pre-synaptic neurons that mediates important binding events to form synapses, the most fundamental unit of neuronal communication. Alterations in neurexin structure underlie many cognitive and neurological diseases. Our limited understanding of neurexin structure hampers our ability to develop targeted therapies to alleviate these disorders. Recent discoveries have found that neurexin is a glycoconjugate decorated with diverse glycosaminoglycan structures. These findings are exciting and prompt the requirement for a comprehensive and glycan-dependent understanding of neurexin structure-binding relationships. However, such studies are challenging, given the diversity and heterogeneity of glycosaminoglycans. Using an innovative proteoglycan editing platform rooted in chemical biology, we will fabricate defined and replete neurexin ectodomains and refine binding relationships with known binding partners (evaluation phase, Aim 1). Subsequently, we will apply these molecules to live primary neurons and display them in a de novo fashion on cell surfaces, such that we can use proximity tagging to capture their corresponding interactomes (discovery phase, Aim 2). These sophisticated materials will serve as important tools to define and evaluate neurexin ligands, and the overall outcome of this application will be a catalogue of neurexin interactomes defined by their glycosylation states.