The role of BARHL2 in the mosaic pattering and dendritic tiling of retinal amacri

BARHL2 在视网膜 amacri 的马赛克图案和树突状平铺中的作用

基本信息

批准号：
8719121
负责人：
Lin Gan
金额：
$ 18.8万
依托单位：
UNIVERSITY OF ROCHESTER
依托单位国家：
美国
项目类别：
财政年份：
2013
资助国家：
美国
起止时间：
2013-09-01 至 2015-08-31
项目状态：
已结题

来源：
https://reporter.nih.gov/project-details/8719121
关键词：
Address Amacrine Cells Axon Blindness Cell Adhesion Molecules Cell Differentiation process Cells ChIP-seq Characteristics Coupled Defect Dendrites Development Down Syndrome Cell Adhesion Molecule Drosophila genus Dyes Ensure Event Exhibits Failure Foundations Future Ganglion Cell Layer Gene Expression Profile Gene Targeting Genes Genetic Individual Injection of therapeutic agent Inner Nuclear Layer Label Link Massive Parallel Sequencing Molecular Morphology Mus Mutant Strains Mice Nervous System Physiology Nervous system structure Neurites Neurons Pathway interactions Pattern Phenotype Play Process Property Protein Kinase Recovery Regulatory Pathway Research Retina Retinal Role Sensory Shotgun Sequencing Staging Structure Technology Time Vision cell type cholinergic chromatin immunoprecipitation density ganglion cell gene discovery homeodomain neural circuit neuronal cell body novel public health relevance response retinal neuron transcription factor transcriptome sequencing visual information

项目摘要

DESCRIPTION (provided by applicant): Our accurate vision depends on the flow of visual information through precisely wired connections between axons and dendrites of different retinal neurons. In the retina, neurons occupy spatial domains and arborize their dendrites, which require the proper distribution of their cell bodies and dendritic arbors. Cell bodies of the same type of neurons are spaced out in a process called mosaic patterning, and their dendrites establish a zone within which other cells of the same type are excluded, a process called tiling. In addition, the neurites from an individual cell display self-avoidance properties. In contrast to the excellent progress made in discovering genes and mechanisms of retinal cell fate determination and differentiation, relatively little is known about the molecular mechanisms underlying the mosaic patterning and tiling processes in the retina as well as in other nervous systems. Not until recently, studies show that in mice mutant for Down syndrome cell adhesion molecule (DSCAM), DSCAM-LIKE1 (DSCAML1), MEG10, and PCDH, certain types of retinal amacrine and ganglion cells exhibit defects in the spacing of cell bodies and in the dendritic arborization, which begins to implicate the roles of unique classes of cell adhesion molecules (CAMs) in regulating these processes in the vertebrate retina. Nevertheless, we have yet to uncover the other molecules involved in these processes in each of the nearly 80 retinal cell types and subtypes, and more importantly, to identify and characterize the entire genes and genetic pathways that govern the formation of functional neural circuitry. In the past, this question has been hard to address due to the lack of a suitable molecule. Here, we show that in mice lacking BARHL2, a BAR-homeodomain transcription factor, starburst amacrine cells in the ganglion cell layer have aggregated dendrites and clumped cell bodies, indicating Barhl2's role in self-avoidance. Being the first transcription factor implicated in neuronal mosaic patterning and tiling processes, BARHL2 offers a unique opportunity to ultimately identify genetic pathways of neuronal mosaic patterning and tiling formation. In this proposal, we will fully characterize th mosaic patterning and tiling phenotypes of starburst amacrine cells in the ganglion cell layer of the Barhl2-null retina. Second, to recover the genetic pathway of self-avoidance, we will perform RNA-Seq of Barhl2 wild type and null starburst amacrine cells and BARHL2 ChIP-Seq to screen for downstream target genes of Barhl2 and to identify the transcriptional network regulating the tiling and mosaic patterning processes of starburst amacrine cells. Together, these studies will define the role of Barhl2 in regulating the tiling and mosaic patterning processes of starburst amacrine cells and elucidate the transcriptional events that occur downstream of Barhl2.

描述（由申请人提供）：我们的准确视力取决于视觉信息的流动，通过轴突和不同视网膜神经元的轴突和树突之间的有线连接。在视网膜中，神经元占据了空间结构域并将其树突塑造出来，这需要其细胞体和树突状乔木的适当分布。相同类型的神经元的细胞体在一个称为镶嵌图案的过程中分布了，其树突建立了一个区域，在该区域中排除了相同类型的其他细胞，这是一个称为瓷砖的过程。另外，来自单个细胞的神经突显示自避免特性。与在发现视网膜细胞命运确定和分化的基因和机制方面取得了良好的进步，对视网膜以及其他神经系统中镶嵌图案和平铺过程的分子机制的了解相对较少。直到最近，研究才表明，在小鼠突变体中，用于唐氏综合征细胞粘附分子（DSCAM），DSCAM-LIKE1（DSCAML1），MEG10和PCDH，某些类型的视网膜链氨酸酯和神经节细胞在细胞体的间距中表现出缺陷，在细胞体的间距中，在树突状养殖体中，构成了一个独特的群体，该类别的独特构成了一系列的独特之处。在脊椎动物视网膜中调节这些过程。然而，我们尚未发现近80种视网膜细胞类型和亚型中的每个过程中涉及的其他分子，更重要的是，识别和表征控制功能神经回路形成的整个基因和遗传途径。过去，由于缺乏合适的分子，这个问题很难解决。在这里，我们表明，在缺乏BARHL2的小鼠中，神经节细胞层中的星状骨骼转录因子的小骨细胞具有聚集的树突和结块的细胞体，表明BARHL2在自我避免中的作用。作为与神经元的镶嵌图案和平铺过程有关的第一个转录因子，Barhl2提供了一个独特的机会，可以最终识别神经元镶嵌图案和瓷砖形成的遗传途径。在此提案中，我们将充分表征Barhl2-null视网膜神经节细胞层中星状骨细胞的镶嵌图案和平铺表型。其次，为了恢复自我避免的遗传途径，我们将执行BARHL2野生型的RNA-Seq和Null Starburst amacrine细胞和BarHL2芯片seq筛选BARHL2的下游靶基因，以识别转录网络的转录网络，以调节Starburst Amacrace Amacrine Almacrine Almacrine细胞的平铺和镶嵌型静态过程。总之，这些研究将定义BARHL2在调节Starburst amacrine细胞的平铺和镶嵌图案过程中的作用，并阐明BARHL2下游发生的转录事件。