THE ROLE OF E2F2 MODULATION OF RB1 IN COCHLEAR HAIR CELLS AND SUPPORTING CELLS

E2F2 对耳蜗毛细胞和支持细胞中 RB1 的调节作用

• 批准号: 7960548
• 负责人: Sonia M Rocha-Sanchez
• 金额: $ 7.92万
• 依托单位: UNIVERSITY OF NEBRASKA MEDICAL CENTER
• 依托单位国家: 美国
• 财政年份: 2009
• 资助国家: 美国
• 起止时间: 2009-09-15 至 2010-06-30
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/7960548
• 关键词: Ablation; Adult; Age; Apoptosis; Birth; Cardiac; Cell Cycle; Cell Cycle Regulation; Cell Proliferation; Cells; Centers of Research Excellence; Cochlea; Computer Retrieval of Information on Scientific Projects Database; Data; Excision; Exhibits; Funding; Genes; Goals; Grant; Hair Cells; Institution; Labyrinth; Mitotic; Molecular Biology; Mus; Natural regeneration; Pattern; Population; Proteins; RB1 gene; Regulator Genes; Research; Research Personnel; Resources; Retinoblastoma; Role; Source; Suggestion; Supporting Cell; System; Technology; United States National Institutes of Health; cell type; hair cell regeneration; neurosurgery; novel; transcription factor; transcriptomics

This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Targeted manipulation of retinoblastoma 1 protein, (pRb or RB1), suggested that Rb1 is required for normal hair cell (HC) cell cycle control, including full differentiation and mitotic quiescence (Mantela et al. 2005; Sage et al. 2005). However, global Rb1 deficient mice die before birth and exhibit an aberrant pattern of cell proliferation in the inner ear. Thus, a targeted excision of Rb1 in inner ear HCs is needed to avoid the deleterious global effects. Specific Rb1 deletion in the mouse HCs was recently shown to cause an aberrant proliferation at an early age, followed by a massive loss of HCs in the adults (Weber et al. 2005; Sage et al. 2006). This suggests that Rb1 imbalance in adult HCs leads to apoptosis, as expected from the deletion of either the Rb1 gene or its associated transcription factors: the E2Fs genes (Ikeda et al. 1996; Kastner et al. 1998; Giangrande et al. 2000; Hallstrom and Nevins 2003; Mantela et al. 2005). Nevertheless, data in the CNS and cardiac cells have shown the ability of some cell populations to re-enter the cell cycle and differentiate without apoptosis, suggesting that the impact of pRb ablation is likely cell-type dependent (Ferguson et al. 2002; MacPherson et al. 2003; Marino et al. 2003; Maclellan et al. 2005). The current results in Rb1 gene manipulation suggest that an alternative approach to study the potential of pRb manipulation for HC regeneration is needed. In order to accomplish this goal we have taken advantage of several of the novel molecular biology technologies which are described more in detail in our original proposal and briefly highlighted in the description of our specific aims (see bellow). Additionally, as per the COBRE internal council's suggestion, two new aims were added to this study. Initially, the potential of Rb1 manipulation in the inner ear hair cells to induce HCs regeneration will be assessed (S.A. 2). Our third aim will consist of using a transcriptomic approach to identify possible gene regulatory network for the differentiation of hair cells and supporting cells in the cochlea. Our ultimate goal is to manipulate postmitotic SC to re-enter the cell cycle and evaluate their potential to spontaneously differentiate into HCs.

这个子项目是许多研究子项目中利用 资源由NIH/NCRR资助的中心拨款提供。子项目和 调查员(PI)可能从NIH的另一个来源获得了主要资金， 并因此可以在其他清晰的条目中表示。列出的机构是 该中心不一定是调查人员的机构。 靶向操作视网膜母细胞瘤1蛋白(PRB或RB1)表明，Rb1是正常毛细胞(HC)细胞周期控制所必需的，包括完全分化和有丝分裂静止(Mantela等人)。2005年；Sage等人。2005)。然而，全球Rb1缺陷小鼠在出生前就会死亡，并在内耳表现出细胞增殖的异常模式。因此，需要有针对性地切除内耳HCS中的Rb1，以避免有害的全局影响。最近发现，小鼠HCS中特定的Rb1缺失会在早期导致异常增殖，随后在成人中会大量丧失HCS(Weber等人。2005年；Sage等人。2006)。这表明成人HCS中Rb1的失衡会导致细胞凋亡，正如Rb1基因或其相关的转录因子E2FS基因的缺失所预期的那样(Ikeda等人。1996年；Kastner等人。1998年；Giangrande等人。2000年；霍尔斯特罗姆和内文斯2003年；曼特拉等人。2005)。然而，中枢神经系统和心脏细胞中的数据显示，某些细胞群能够重新进入细胞周期并在没有凋亡的情况下分化，这表明PRB消融的影响可能是细胞类型相关的(Ferguson等人。2002年；麦克弗森等人。2003年；Marino等人。2003年；Maclellan等人。2005)。目前Rb1基因操作的结果表明，需要一种替代的方法来研究pRb操作对HC再生的潜力。为了实现这一目标，我们利用了几种新的分子生物学技术，这些技术在我们最初的提案中有更详细的描述，在我们的具体目标的描述中也有简要的强调(见下文)。此外，根据科布雷内部委员会的建议，这项研究增加了两个新的目标。首先，将评估在内耳毛细胞中操纵Rb1诱导HCS再生的潜力(S.A2)。我们的第三个目标将包括使用转录学方法来确定可能的基因调控网络，以分化耳蜗毛细胞和支持细胞。我们的最终目标是操纵有丝分裂后的SC重新进入细胞周期，并评估它们自发分化为HC的潜力。