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

• 批准号: 8585275
• 负责人: Lin Gan
• 金额: $ 23.03万
• 依托单位: UNIVERSITY OF ROCHESTER
• 依托单位国家: 美国
• 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/8585275
• 关键词: Address; Amacrine Cells; Axon; Blindness; Cell Adhesion Molecules; Cell Differentiation process; Cells; ChIP-seq; Characteristics; Coupled; DNA Sequence; 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; 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

PROJECT SUMMARY 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 the 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.

项目摘要 我们准确的视觉取决于视觉信息通过精确的有线连接的流动 不同视网膜神经元的轴突和树突之间的联系。在视网膜中，神经元占据空间域， 树枝状化它们的树突，这需要它们的细胞体和树突树枝的适当分布。细胞 同一类型的神经元的身体在一个称为马赛克图案的过程中间隔开， 建立一个区域，在该区域内排除相同类型的其他细胞，这一过程称为平铺。此外该 来自单个细胞的神经突显示出自我回避特性。与取得的出色进展相比， 发现视网膜细胞命运决定和分化的基因和机制，相对而言知之甚少 关于视网膜中马赛克图案和平铺过程的分子机制，以及 其他神经系统。直到最近，研究表明，在小鼠中，唐氏综合症细胞的突变 粘附分子（DSCAM）、DSCAM样1（DSCAML 1）、MEG 10和PCDH，某些类型的视网膜 无长突细胞和神经节细胞在细胞体的间隔和树突状分支中表现出缺陷， 开始暗示独特类别的细胞粘附分子（CAM）在调节这些细胞粘附分子中的作用。 脊椎动物视网膜上的突起。尽管如此，我们还没有发现参与这些的其他分子。 过程中的每一个近80视网膜细胞类型和亚型，更重要的是，以确定和 描述了控制功能性神经回路形成的整个基因和遗传途径。在 过去，由于缺乏合适的分子，这个问题一直难以解决。在这里，我们表明，在 缺乏BARHL 2（一种BAR同源结构域转录因子）的小鼠，神经节细胞中的星状无长突细胞 层具有聚集的树突和聚集的细胞体，表明Barhl 2在自我回避中的作用。作为 第一个涉及神经元镶嵌图案和平铺过程的转录因子，BARHL 2提供了一个独特的 有机会最终确定神经元镶嵌图案和平铺形成的遗传途径。在这 我们将充分描述星爆无长突细胞的镶嵌图案和平铺表型， Barhl 2缺失视网膜的神经节细胞层。其次，为了恢复自我回避的遗传途径，我们 将进行Barhl 2野生型和无效星爆无长突细胞的RNA-Seq和BARHL 2 ChIP-Seq以筛选 Barhl 2的下游靶基因，并鉴定调控平铺的转录网络， 星爆状无长突细胞的镶嵌图案化过程。总之，这些研究将确定Barhl 2的作用， 调节星爆无长突细胞的平铺和镶嵌图案化过程，并阐明 Barhl 2下游发生的转录事件。