The role of adaptor proteins in endosomal sorting during ultrafast endocytosis

接头蛋白在超快内吞过程中内体分选中的作用

• 批准号: 10232091
• 负责人: Kevin Jonathan Kruse
• 金额: $ 6.64万
• 依托单位: UNIVERSITY OF UTAH
• 依托单位国家: 美国
• 财政年份: 2020
• 资助国家: 美国
• 起止时间: 2020-09-01 至 2022-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/10232091
• 关键词: Actin-Binding Protein; Actins; Adaptor Signaling Protein; Alleles; Alzheimer' s Disease; Animals; Ataxia; Auxins; Binding; Biochemical Genetics; Biological; Biological Process; CRISPR/Cas technology; Caenorhabditis elegans; Cell membrane; Cells; Clathrin; Clathrin Adaptor Protein Complexes; Color; Complex; Cytoskeleton; Cytosol; Defect; Diffuse; Electron Microscopy; Endocytic Vesicle; Endocytosis; Endosomes; Exhibits; Exposure to; FASTK Gene; Failure; Fellowship; Fluorescence; Freezing; Genes; Genetic; Goals; Hippocampus (Brain); Hot Spot; Huntington Disease; Location; Lysosomes; Mediating; Membrane; Methods; Microscopy; Morphology; Mus; Mutation; Natural regeneration; Nematoda; Neurodegenerative Disorders; Neuromuscular Junction; Neurons; Neurotransmitter Receptor; Parkinson Disease; Pathway interactions; Play; Process; Proteins; Recovery; Recycling; Resolution; Role; Sampling; Scaffolding Protein; Site; Sorting - Cell Movement; Specificity; Synapses; Synaptic Vesicles; Syndrome; Time; Tissues; Transcription Factor AP-1; Vesicle; enhancer-binding protein AP-2; genetic approach; intersectin 1; macromolecule; mutant; nano; neurotransmission; overexpression; pleiotropism; receptor; synaptic function; trafficking

Summary Endocytosis is a process by which macromolecules, receptors, transporters, and channels are recycled via internalization of the plasma membrane. Endocytosis at synapses, called synaptic vesicle endocytosis, supports the rapid recovery of vesicles during neurotransmission. Clathrin-mediated endocytosis occurs ~ 30 s after stimulation, however using “flash-and-freeze” electron microscopy we have demonstrated endocytosis at 30 – 300 ms after stimulation in both mouse hippocampal neurons as well as C. elegans neuromuscular junctions. Further, the process is clathrin independent. Ultrafast endocytosis generates a large endosome, which much be sorted into new synaptic vesicles or targeted for degradation in the lysosomes. Sorting of the endosome requires clathrin, but it is not clear which proteins act on the endosome to target these vesicles. The clathrin binding adaptor proteins AP1, AP2, and AP3 have all been implicated in synaptic function and targeting of membrane bound compartments. AP2 is thought to regenerate synaptic vesicles, while AP1 and AP3 are thought to target vesicles to the plasma membrane or the lysosome, respectively. The goal of this fellowship is to determine the role of these adaptor proteins in endosomal sorting and regeneration of synaptic vesicles during ultrafast endocytosis.

概括 内吞作用是大分子、受体、转运蛋白和 通道通过质膜的内化进行再循环。内吞作用 突触，称为突触小泡内吞作用，支持小泡的快速恢复 在神经传递过程中。刺激后约 30 秒发生网格蛋白介导的内吞作用， 然而，使用“闪冻”电子显微镜我们已经证明 刺激后 30 – 300 ms 小鼠海马神经元也发生内吞作用 作为秀丽隐杆线虫的神经肌肉接头。此外，该过程是独立于网格蛋白的。 超快的内吞作用产生一个大的内体，它被分类成新的 突触小泡或溶酶体中的降解目标。内体的分选 需要网格蛋白，但尚不清楚哪些蛋白质作用于内体以靶向这些蛋白 囊泡。网格蛋白结合接头蛋白 AP1、AP2 和 AP3 均已被 涉及突触功能和膜结合区室的靶向。 AP2 是 据认为可以再生突触小泡，而 AP1 和 AP3 则被认为以小泡为目标 分别到达质膜或溶酶体。该奖学金的目标是 确定这些衔接蛋白在内体分选和再生中的作用 超快内吞作用期间的突触小泡。