EAPSI: Determining the Atomic Structure of Proteins that Form Brain Connections

大脑通过一组被称为神经元的特殊细胞进行交流并形成记忆。这些细胞通过称为神经突起的延伸形成联系。当神经元改变其蛋白质骨架以接触其他细胞时，就形成了神经突起。细胞骨架的破坏会损害记忆的形成。Tropomodulins(Tmods)是一个蛋白质家族，参与神经元细胞骨架的形成。在癫痫发作、中风、接触甲基苯丙胺以及唐氏综合症和癫痫期间，大脑中Tmods的数量已显示出极大的变化。了解Tmods在大脑发育中的作用将阐明这些情况，并可能导致治疗。先前的研究表明，Tmods在轴突形成中作用的变化与结构差异有关。该项目的目标是确定Tmod2的原子结构(蛋白质功能中的决定因素)，以便与Tmod1的已知结构进行比较。该项目将与日本冲绳科学技术研究所蛋白质结构专家Fadel Samatey博士合作进行。已解决的Tmod2结构将揭示Tmods在大脑发育和疾病状态中断中微调作用的细节。结晶和X射线衍射是将用于确定蛋白质结构的技术。本项目旨在筛选和优化Tmod2的富亮氨酸重复序列(LRR)结构域的结晶条件，然后通过X射线衍射确定其结构。这个结构域对Tmod在肌肉细胞中的定位、胸腺素结合和Tmod的肌动蛋白成核能力都是重要的。对Tmod结构的比较将导致突变的残基，这将把这些蛋白质的结构与它们在轴突形成中的作用联系起来。该NSF EAPSI奖是与日本科学促进会合作资助的。

The brain communicates and forms memories through a specialized group of cells called neurons. These cells form connections through extensions called neurites. Neurites are formed when neurons alter their protein skeleton to reach for other cells. Disruptions to the cellular skeleton can harm memory formation. Tropomodulins (Tmods) are a family of proteins that contribute to the formation of the cellular skeleton in neurons. During seizures, strokes, and methamphetamine exposure and also in Down syndrome and epilepsy, the amounts of Tmods in the brain have been shown to be vastly altered. Understanding the role of Tmods in brain development will elucidate these conditions and may lead to treatments. Previous studies have shown that variation in Tmods' roles in neurite formation correlates with structural differences. The goal of this project is to determine the atomic structure (determinant in protein function) of Tmod2 for comparison with the known structure of Tmod1. This project will be conducted in collaboration with Dr. Fadel Samatey, an expert in protein structure at the Okinawa Institute of Science and Technology in Japan. A solved structure for Tmod2 will uncover details about Tmods' finely tuned role in brain development and disruption in disease states. Crystallization and X-ray Diffraction are techniques that will be used to determine protein structure. This project aims to screen for and optimize crystallization conditions for the leucine rich repeat (LRR) domain of Tmod2 and then determine its structure by X-ray Diffraction. This domain is important for localization of Tmods in muscle cells, thymosin binding and Tmod's actin nucleation ability. Comparison of Tmod structures will lead to residues for mutagenesis that will connect the structure of these proteins to their roles in neurite formation. This NSF EAPSI award is funded in collaboration with the Japan Society for the Promotion of Science.