Role of Sox2 in Specification of Prosensory and Hair Cell Fate in Mouse Cochlea

Sox2 在小鼠耳蜗前感觉和毛细胞命运规范中的作用

• 批准号: 8391189
• 负责人: Chandrakala Puligilla
• 金额: $ 23.66万
• 依托单位: MEDICAL UNIVERSITY OF SOUTH CAROLINA
• 依托单位国家: 美国
• 财政年份: 2011
• 资助国家: 美国
• 起止时间: 2011-12-01 至 2014-11-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/8391189
• 关键词: Actins; Address; Adherens Junction; Adhesions; Animals; Automobile Driving; Award; Binding; Biological Assay; Biologically Based Therapy; Blocking Antibodies; Cadherins; Cell Adhesion; Cell Adhesion Molecules; Cell Differentiation process; Cell Line; Cell Nucleus; Cell-Cell Adhesion; Cells; Cochlea; Cochlear Implants; Complex; Culture Media; Cytoplasmic Tail; Cytoskeleton; DNA; Data; Defect; Development; Dominant-Negative Mutation; E-Cadherin; E-Cadherin Staining Method; Ectoderm; Ectopic Expression; Electroporation; Elements; Embryo; Epithelial Cells; Epithelium; Extracellular Domain; Gene Targeting; Generations; Genetic Transcription; Genotype; Glial Fibrillary Acidic Protein; Goals; Hair Cells; Head; Hearing; Heterozygote; Immunohistochemistry; In Vitro; Inner Hair Cell of the Organ of the Corti; Inner Hair Cells; Inner Supporting Cell; Knowledge; Labyrinth; Lead; Link; MDCK cell; Maintenance; Mediating; Molecular; Morphology; Multipotent Stem Cells; Mus; N-Cadherin; Nuclear Translocation; Organ; Organ of Corti; Outer Hair Cells; Partner in relationship; Pathway interactions; Pattern; Personal Communication; Phase; Phenotype; Play; Positioning Attribute; Process; Recovery; Regulation; Research; Research Design; Role; Sensory; Sensory Hair; Signal Pathway; Signal Transduction; Staging; Stem cells; Supporting Cell; System; Tail; Tamoxifen; Techniques; Testing; Time; base; cell determination; cell fate specification; cell type; chromatin immunoprecipitation; embryo culture; hearing impairment; in vivo; insight; loss of function; mutant; neuroblast; novel; otoconia; overexpression; progenitor; programs; promoter; regenerative; research study; transcription factor; vector

A key step in the development of inner ear sensory epithelia is the commitment of multipotent progenitor cells in otocyst to a prosensory fate, defined by the ability to give rise to either hair cells or support cells. However, the factors that confer prosensory fate to these cells are only beginning to be identified. Recent studies have shown that the HMG class transcription factor Sox2 is dynamically expressed in prosensory cells and is required for the formation of this cell type. However, the specific roles of Sox2, and in particular whether it can induce prosensory identity, has not been determined. The main goals of the experiments described in this proposal are to use a combination of in vivo and in vitro approaches to determine the specific effects of Sox2 during cochlear development and further, to determine whether some or all of these effects are mediated through the candidate downstream effectors, Proxl, E-cadherin, and N-cadherin. During the K99 phase of the award, progress has been made towards the completion of all three aims. The first aim that was proposed as part of K99 focussed on the specific roles of Sox2 in regulating prosensory, and ultimately hair cell specification. Our results demonstrate that transient activation of Sox2 leads to ectopic hair cell formation, suggesting a direct role of Sox2 in the induction of Atohl, a conclusion that was confirmed by chromatin immunoprecipitation analysis. In addition, our data show that induction of prosensory identity is essential for hair cell formation and that hair cells must go through a "prosensory cell" phase prior to hair cell differentiation. In the second aim, the relationship between Sox2 and the putative Sox2-target gene, E-cadherin, will be examined. Gain- & loss-of function in vivo and in vitro experiments will be used to determine whether the effects of Sox2 on cell fate and patterning are mediated through E-cadherin. In the final aim, the role of N-cadherin, a known target of Sox2, in determination of cell fate and cellular patterning will be examined. Moreover, experiments examining the specific effects of modulation of E-cadherin and Ncadherin signaling & the relationship of these two molecules to Sox2 should provide insights into the signaling pathways that direct cells towards hair cell fate.

内耳感官上皮的发展的关键步骤是多能祖细胞的承诺 耳细胞中的细胞到处相性命运，由产生毛细胞或支持细胞的能力定义。 但是，赋予这些细胞的处相性命运的因素才被开始鉴定出来。最近的 研究表明，HMG类转录因子SOX2在ProSensory中动态表达 细胞，是形成该细胞类型所必需的。但是，Sox2的具体角色，尤其是 它是否可以诱导处相身份，尚未确定。实验的主要目标 本提案中描述的是使用体内和体外方法的组合来确定 Sox2在人工耳蜗开发过程中的特定影响，进一步确定是否是某些或全部 效应是通过候选效应子Proxl，E-Cadherin和N-钙粘着蛋白介导的。 在奖项的K99阶段，在完成这三个目标的完成方面取得了进展。这 作为K99的一部分提出的第一个目标，侧重于Sox2在调节Prostensory中的特定作用， 并最终是毛细胞规格。我们的结果表明，Sox2的瞬时激活导致 异位毛细胞形成，表明Sox2在Atohl诱导中的直接作用，这是一个结论 通过染色质免疫沉淀分析确认。此外，我们的数据表明，体育型的诱导 身份对于毛细胞的形成至关重要，毛细胞必须在先前经过“处相细胞”阶段 到毛细胞分化。在第二个目标中，Sox2与推定的Sox2-Target之间的关系 将检查基因，电子钙粘蛋白。体内和体外实验的功能损失将用于 确定SOX2对细胞命运和模式的影响是否通过E-钙粘着蛋白介导。在 最终目的是N-钙粘蛋白（已知的SOX2靶标）在细胞命运和细胞模式中的作用 将被检查。此外，研究了E-钙粘蛋白和NCADHERIN调节的特定效应的实验 这两个分子与Sox2的信号传导和关系应提供洞察力 信号通路将细胞引向毛细胞命运。