Mechanisms regulating the plasticity of postmitotic cells in mammalian retina

调节哺乳动物视网膜有丝分裂后细胞可塑性的机制

• 批准号: 10610823
• 负责人: Sui Wang
• 金额: $ 40.14万
• 依托单位: STANFORD UNIVERSITY
• 依托单位国家: 美国
• 财政年份: 2021
• 资助国家: 美国
• 起止时间: 2021-05-01 至 2026-04-30
• 项目状态: 未结题
• 来源: https://reporter.nih.gov/project-details/10610823
• 关键词: Adult; Binding; Biology; Candidate Disease Gene; Cell Reprogramming; Cells; Data; Defect; Development; Disease; Down-Regulation; Ectopic Expression; Electroporation; Embryo; Ensure; Family; Functional disorder; Genes; Gliosis; Human; Interneurons; Light; Methods; Microphthalmos; Microscopy; Mitotic; Muller' s cell; Mus; Mutation; Myelin; Neonatal; Neuroglia; Neurons; Notch Signaling Pathway; Pathway interactions; Play; Production; Promoter Regions; Proteins; Publishing; Repression; Retina; Retinal Diseases; Role; Stereotyping; Testing; Therapeutic; Titrations; Work; Zinc Fingers; cell fate specification; cell type; developmental disease; gain of function; genetic approach; improved; in vivo; loss of function; member; neurogenesis; novel; plasmid DNA; postmitotic; postnatal; programs; regenerative therapy; retinal neuron; retinal progenitor cell; retinal regeneration; single-cell RNA sequencing; spine bone structure; tool; transcription factor

PROJECT SUMMARY/ABSTRACT One of the promising strategies to treat retinal diseases is to generate desired neuronal types, which are damaged or lost during disease, and develop cell replacement-based therapies. A comprehensive understanding of how distinct retinal types are formed during development can greatly inform these therapeutic strategies. While mitotic retinal progenitor cells (RPCs) are thought to be intrinsically different, the fates of retinal cells are not determined in RPCs. Many newly born postmitotic cells are still plastic. It is currently not clear how newly born postmitotic cells attain their final fate states. We propose to uncover the genes and pathways that regulate fate decisions in newly born postmitotic cells during development and determine whether they can also promote cell reprogramming in adult retina. We collected genes that are enriched in newly born postmitotic cells in the retina based on published single cell RNA-seq data, and developed novel methods to study their function specifically in newly born postmitotic cells in vivo by utilizing retroviral-based genetic approach and light sheet microscopy. A zinc finger transcription factor Myt1 (Myelin transcription factor 1) was found to be enriched in newly born postmitotic cells, but not RPCs, during development; it can promote neurogenesis, especially the formation of bipolar cells, while repressing glial fate in newly born postmitotic cells at neonatal stages. We hypothesize that Myt1 ensures the neuronal fates in newly born postmitotic cells and can contribute to neuronal reprogramming in mature retina. In the proposed studies, we will test this hypothesis through two aims. In Aim1, we will elucidate the function of Myt1 in fate determination, and test the hypothesis that Myt1 promotes bipolar cell fates by titrating down, but not completely shutting down Notch signaling pathway, and by actively repressing glial genes in newly born postmitotic cells. In Aim2, we will determine whether Myt1 together with Ascl1 and Brn2 can promote direct reprogramming of Müller glial cells into neurons in mature mouse retina. Taken together, this proposal aims to elucidate the plasticity of postmitotic cells in mammalian retina. We will focus on understanding how zinc finger transcription factor Myt1 promotes specific neuronal fates in newly born postmitotic cells during development and determining whether Myt1 can enhance neuronal reprogramming from glial cells in mature retina. This work will improve our understanding of basic biology and provide new candidate genes and possibilities for the regeneration of retinal neurons. Notably, mutations in human Myt1 gene are associated with Oculo-Auriculo-Vertebral Spectrum diseases, which are developmental disorders with ocular defects such as microphthalmia. Elucidating the function of Myt1 in retinal development can also shed light on the disease mechanisms.

项目总结/摘要 治疗视网膜疾病的有希望的策略之一是产生期望的神经元类型，其是 在疾病期间受损或丢失，并开发基于细胞增殖的疗法。全面 了解不同的视网膜类型在发育过程中是如何形成的，可以极大地告知这些治疗方法。 战略布局虽然有丝分裂的视网膜祖细胞（RPC）被认为是本质上不同的，但它们的命运是不同的。 在RPC中不确定视网膜细胞。许多新生的有丝分裂后细胞仍然是可塑的。目前暂不 清楚新生的有丝分裂后细胞如何达到其最终的命运状态。我们打算揭开基因， 在发育过程中调节新生有丝分裂后细胞命运决定的途径， 它们是否也能促进成人视网膜中的细胞重编程。 我们收集的基因是丰富的新生有丝分裂后细胞在视网膜上的基础上发表的 单细胞RNA-seq数据，并开发了新的方法来研究他们的功能，特别是在新生儿 有丝分裂后的细胞在体内通过利用逆转录病毒为基础的遗传方法和光片显微镜。锌指 发现转录因子Myt 1（髓磷脂转录因子1）在新生的有丝分裂后细胞中富集， 但不是RPC，在发育过程中，它可以促进神经发生，特别是双极细胞的形成， 在新生期抑制新生有丝分裂后细胞中的神经胶质命运。我们假设Myt 1确保了 在新生的有丝分裂后细胞中的神经元命运，并且可以有助于成熟视网膜中的神经元重编程。 在拟议的研究中，我们将通过两个目标来验证这一假设。在目标1中，我们将阐明 Myt 1在命运决定中的作用，并检验Myt 1通过滴定降低而促进双极细胞命运的假设， 不完全关闭Notch信号通路，并通过主动抑制新生儿中的神经胶质基因， 有丝分裂后细胞在Aim 2中，我们将确定Myt 1与Ascl 1和Brn 2一起是否可以直接促进 Müller神经胶质细胞在成熟小鼠视网膜中重编程为神经元。 总之，这一建议的目的是阐明哺乳动物视网膜有丝分裂后细胞的可塑性。我们 将专注于了解锌指转录因子Myt 1如何促进新的神经元的特定命运。 在发育过程中出生的有丝分裂后细胞，并确定Myt 1是否可以增强神经元 从成熟视网膜中的神经胶质细胞重编程。这项工作将提高我们对基础生物学的理解， 为视网膜神经元的再生提供了新的候选基因和可能性。值得注意的是， 人Myt 1基因与眼耳脊椎谱系疾病相关，这些疾病是发育性 具有眼部缺陷的疾病，例如小眼症。Myt 1在视网膜发育中的作用 还可以揭示疾病机制。