Intercellular Signaling and Endosome to Golgi Transport in Multicellular Animals

多细胞动物的细胞间信号传导和内体到高尔基体的运输

• 批准号: 8608558
• 负责人: Barth Demian Grant
• 金额: $ 29.45万
• 依托单位: RUTGERS, THE STATE UNIV OF N.J.
• 依托单位国家: 美国
• 财政年份: 2013
• 资助国家: 美国
• 起止时间: 2013-02-01 至 2017-01-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8608558
• 关键词: AMPA Receptors; Actins; Alzheimer' s Disease; Animals; Apoptotic; Binding; Caenorhabditis elegans; Cell membrane; Cell physiology; Cells; Centers for Disease Control and Prevention (U.S.); Clathrin; Collaborations; Complex; Copper; Data; Development; Disease; Drosophila genus; Endosomes; Epithelial; Event; Feedback; Generations; Genetic Screening; Goals; Golgi Apparatus; Guanosine Triphosphate Phosphohydrolases; Health; Human; IGF Type 2 Receptor; Immunity; Ligands; Link; Lysosomal Storage Diseases; Lysosomes; Malignant Neoplasms; Mammalian Cell; Mediating; Membrane; Menkes Kinky Hair Syndrome; Metabolism; Microscopic; Molecular; Molecular Chaperones; Nematoda; Nervous system structure; Organism; PARD6A gene; Parkinson Disease; Pathogenicity; Pathway interactions; Phylogenetic Analysis; Process; Proteins; RNA Interference; Receptor Signaling; Recycling; Regulation; Research; Retrieval; Ricin; Role; SH3 Domains; Signal Pathway; Signal Transduction; Sorting - Cell Movement; System; Tertiary Protein Structure; Testing; Toxin; Transducers; WAVE protein; Work; Yeasts; combat; disorder control; genetic regulatory protein; genome-wide; improved; insight; intestinal epithelium; mutant; novel; protein complex; protein function; public health relevance; receptor; retrograde transport; therapeutic target; trafficking

DESCRIPTION (provided by applicant): Our long-term goal in this proposal is to identify and understand the cellular components that transport internalized endocytic cargo from endosomes to the Golgi apparatus (retrograde recycling), and to understand how this process regulates, and is integrated within, intercellular signaling pathways. Retrograde recycling has recently been linked to multiple metazoan-specific processes such as the generation of Wnt signaling gradients, AMPA-receptor signaling in the nervous system, clearance of dead apoptotic cells, and regulation of epithelial polarity. Wnt signaling requires endosome-to-Golgi retrieval of the Wnt ligand chaperone MIG-14/Wntless, and the molecular details of MIG-14/Wntless recycling have proven to be highly conserved in C. elegans, Drosophila, and mammalian cells. Without retrograde recycling, transmembrane cargo proteins such as MIG-14/Wntless aberrantly enter the lysosome and are degraded, thus depleting the functional pool of such proteins from the cell. To gain novel insight into how retrograde recycling functions, and how it influences intercellular signaling mechanisms in multicellular animals, we have pioneered analysis of the polarized intestinal epithelium of C. elegans. In novel preliminary work we discovered that TGF?-signaling is impaired in retrograde recycling mutants. We plan to further test the hypothesis that TGF?-receptors are retrograde cargo, and test phylogenetic conservation of this mechanism in Drosophila and mammalian cells. In addition, our team has discovered previously unsuspected requirements for endosome regulatory proteins beyond the well-studied retromer complex. These novel regulators include the J-domain co-chaperone RME-8. We plan to test the hypothesis that RME-8 regulates the disassembly of the endosomal flat clathrin lattice, mediating a feedback loop between retromer and the ESCRT-driven degradation machinery that is present on the same endosomes. In addition we have identified an entire additional protein complex involved in retrograde recycling of MIG-14/Wntless. This protein complex appears to be associated with the recycling endosome, and contains modules for membrane binding, membrane bending, and actin nucleation. We plan to determine how this protein complex influences MIG-14/Wntless recycling, test its ability to influence other retrograde cargo including TGF?-receptors, and test for conservation of function in mammalian cells. We expect that our findings will provide unique insight into how trafficking mechanisms influence signaling pathways, and will improve our ability to treat diverse diseases that arise from misregulation of receptor signaling strength, such as in cancers, and other diseases associated with misregulated retrograde recycling including Alzheimer's and Parkinson's diseases.

描述（由申请人提供）：我们在该提案中的长期目标是鉴定和理解将内化的内吞货物从内体运输到高尔基体（逆行再循环）的细胞组分，并了解该过程如何调节和整合在细胞间信号传导通路中。逆行再循环最近已被链接到多个后生动物的特定过程，如Wnt信号梯度的产生，AMPA受体信号在神经系统中，死亡的凋亡细胞的清除，和上皮极性的调节。Wnt信号传导需要Wnt配体伴侣蛋白<$14/Wntless的内体到高尔基体的回收，并且<$14/Wntless回收的分子细节已被证明在C.线虫、果蝇和哺乳动物细胞。在没有逆行再循环的情况下，跨膜货物蛋白如β-14/Wntless异常地进入溶酶体并被降解，从而从细胞中耗尽这些蛋白质的功能库。为了深入了解逆行循环的功能，以及它如何影响多细胞动物的细胞间信号传导机制，我们率先分析了C。优雅的在新的初步工作中，我们发现TGF？信号传导在逆行再循环突变体中受损。我们计划进一步检验TGF？受体是逆行货物，并测试果蝇和哺乳动物细胞中这种机制的系统发育保守性。此外，我们的团队已经发现了先前未被怀疑的要求，超出了充分研究的retromer复合物的内体调节蛋白。这些新的调节剂包括J结构域共分子伴侣RME-8。我们计划测试RME-8调节内体平坦网格蛋白晶格的分解，介导retromer和存在于相同内体上的ESCRT驱动的降解机制之间的反馈回路的假设。此外，我们已经确定了一个完整的额外的蛋白质复合物参与逆行回收的β-14/Wntless。这种蛋白质复合物似乎与再循环内体相关，并且包含用于膜结合、膜弯曲和肌动蛋白成核的模块。我们计划确定这种蛋白质复合物如何影响TGF-14/Wntless循环，测试其影响其他逆行货物的能力，包括TGF？受体，并测试哺乳动物细胞中的功能保守性。我们希望我们的研究结果将为贩运机制如何影响信号通路提供独特的见解，并将提高我们治疗由受体信号强度失调引起的各种疾病的能力，例如癌症，以及其他与失调逆行循环相关的疾病，包括阿尔茨海默病和帕金森病。