The Coordination of Netrin Signal Transduction

Netrin信号转导的协调

• 批准号: 8179622
• 负责人: Guofa Liu
• 金额: $ 43.65万
• 依托单位: UNIVERSITY OF TOLEDO
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-05-01 至 2014-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8179622
• 关键词: Axon; Binding; Biochemical; Biological Assay; Brain; Cells; Cerebellum; Chick Embryo; Complex; Cues; Data; Development; Disease; Down Syndrome Cell Adhesion Molecule; Electroporation; Embryo; Embryonic Development; Family; Goals; Immunoblotting; Immunoglobulins; In Vitro; Injury; Integral Membrane Protein; Light; MAPK8 gene; Mediating; Mitogen-Activated Protein Kinases; Molecular; Mus; Nervous system structure; Neuraxis; Neurons; PTK2 gene; Phosphorylation; Play; Protein Kinase; Proteins; Rattus; Regulation; Role; Signal Transduction; Spinal; Spinal Cord; Spinal cord injury; Stroke; Subgroup; Tyrosine Phosphorylation; Vertebrates; angiogenesis; axon guidance; base; design; human NTN1 protein; member; migration; netrin receptor; netrin-1; neural circuit; neuronal guidance; receptor; research study; response; src-Family Kinases; tool; tumorigenesis

DESCRIPTION (provided by applicant): Netrins, a family of secreted proteins, are not only required for axon guidance and neuronal migration during development, but are also involved in angiogenesis and tumorigenesis. Recent studies including ours indicate that DSCAM (Down syndrome cell adhesion molecule), a transmembrane protein of the immunoglobulin superfamily, functions as a new netrin receptor required for spinal cord commissural axon outgrowth and pathfinding. This application proposes to investigate the molecular mechanisms mediating neuronal responses to netrin-1 with a focus on studying the coordination of signal transduction cascades downstream of different netrin receptors, for instance, DCC, DSCAM and UNC5. Aim 1. Determine the coordinating role of JNK1 in netrin signaling. Our preliminary results suggest that JNK1 is involved in netrin signaling. To further characterize the coordinating role of JNK1 in DCC and DSCAM downstream signaling, we plan to examine the regulation of JNK1 activity by netrin-1 in HEK293 cells and primary neurons, as well as the functional importance of JNK1 in netrin-induced axon outgrowth and attraction. Aim 2. Untangle the coordination of protein phosphorylation in netrin signaling. Protein phosphorylation plays a critical role in netrin signaling during embryonic development. To study the coordination of signal transduction cascades downstream of DSCAM and DCC, we will examine the regulation of protein phosphorylation in netrin/DSCAM signaling, the coordination of protein phosphorylation in netrin/DSCAM and netrin/DCC signaling, relationship of Src family kinases and JNK1 in netrin signal transduction cascades and the functional coordination of DSCAM and DCC in netrin-induced axon outgrowth and attraction. Aim 3. Investigate the coordination of DSCAM and UNC5 in netrin-mediated repulsion. Netrin-1 can act as an attractant or repellent in axon guidance and neuronal migration, depending on when it binds to UNC5. DSCAM forms a receptor complex with UNC5C in HEK293 cells and primary neurons, indicating that they may coordinate in netrin-mediated neuronal repulsion. We plan to examine the distribution and co-localization of DSCAM and UNC5C in the developing nervous system, the coordination of netrin/DSCAM and netrin/UNC5C downstream signaling and the functional role of DSCAM in netrin-mediating axon repulsion. These experiments will shed new light on the coordination of netrin downstream signal transduction cascades and help us better understand how the brain establishes its complex and precise wiring during development. PUBLIC HEALTH RELEVANCE: Coordination of signal transduction cascades downstream of guidance cues is crucial for neurons to find their targets and establish neural circuitry in the developing nervous system. The secreted proteins netrins are prototypical guidance cues for projecting axons and migrating neurons. Studying signal transduction of netrins will not only help us understand how the brain establishes its complex and precise wiring during development, but also provide a basis to design new strategies for injury-related diseases, such as stroke and spinal cord injuries.

描述（由申请人提供）：Netrins是一种分泌蛋白家族，不仅在发育过程中需要轴突引导和神经元迁移，而且还参与血管生成和肿瘤发生。包括我们在内的最近研究表明，DSCAM（唐氏综合征细胞粘附分子）是免疫球蛋白超家族的跨膜蛋白，是脊髓联合轴突生长和寻路所需的一种新的网状蛋白受体。本申请拟探讨神经元对netrin-1反应的分子机制，重点研究不同netrin受体（如DCC、DSCAM和UNC5）下游信号转导级联的协调。目的1。确定JNK1在网络蛋白信号传导中的协调作用。我们的初步结果表明JNK1参与了网络蛋白信号传导。为了进一步表征JNK1在DCC和DSCAM下游信号传导中的协调作用，我们计划研究netrin-1在HEK293细胞和原代神经元中对JNK1活性的调节，以及JNK1在netrin诱导的轴突生长和吸引中的功能重要性。目标2。解开网络蛋白信号中蛋白磷酸化的协调。在胚胎发育过程中，蛋白磷酸化在netrin信号传导中起着关键作用。为了研究DSCAM和DCC下游信号转导级联的协调性，我们将研究netrin/DSCAM信号通路中蛋白磷酸化的调控、netrin/DSCAM和netrin/DCC信号通路中蛋白磷酸化的协调性、Src家族激酶和JNK1在netrin信号转导级联中的关系以及DSCAM和DCC在netrin诱导的轴突生长和吸引中的功能协调性。目标3。研究DSCAM和UNC5在网络介导排斥中的协同作用。Netrin-1可以在轴突引导和神经元迁移中起到引诱剂或驱避剂的作用，这取决于它何时与UNC5结合。DSCAM与UNC5C在HEK293细胞和原代神经元中形成受体复合物，表明它们可能在神经元介导的神经元排斥中协同作用。我们计划研究DSCAM和UNC5C在发育中的神经系统的分布和共定位，netrin/DSCAM和netrin/UNC5C下游信号的协调以及DSCAM在网络介导的轴突排斥中的功能作用。这些实验将为神经网络下游信号转导级联的协调提供新的线索，并帮助我们更好地理解大脑在发育过程中如何建立复杂而精确的线路。