DIFFERENTIATION OF OLFACTORY RECEPTOR NEURONS IN CULTURE

培养中嗅觉受体神经元的分化

• 批准号: 6238159
• 负责人: SARAH K PIXLEY
• 金额: $ 20.16万
• 依托单位: UNIVERSITY OF MARYLAND BALTIMORE
• 依托单位国家: 美国
• 财政年份: 1997
• 资助国家: 美国
• 起止时间: 1997-09-01 至 1998-08-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6238159
• 关键词: astrocytes; biomarker; cell cell interaction; cell cycle; cell differentiation; cell growth regulation; chemoreceptors; cilium; developmental neurobiology; dyes; electron microscopy; electrophysiology; immunocytochemistry; immunoperoxidase; in situ hybridization; laboratory mouse; laboratory rat; mixed tissue /cell culture; neurogenesis; olfactions; olfactory lobe; olfactory stimulus; respiratory epithelium; tissue /cell culture; transforming growth factors

The anatomical, molecular and functional properties that characterize different stages of differentiation of the mammalian olfactory receptor neurons (ORNs) are not well understood. In addition, little is known about the control systems regulating movement from one differentiation stage to another. To characterize ORN differentiation stages and identify regulatory signals, we have developed dissociated cell culture systems of newborn and adult rat nasal cells. In these cultures, ORNs are generated and undergo both initial differentiation and maturation (electrical responses to odorants and expression of the olfactory marker protein). This is the only dissociated culture system described to date that shows maturation of ORNs. Our preliminary data have shown or suggested that ORNs have several stages of differentiation, that neurogenesis and differentiation are under separate regulatory control, and that specific bulb-epithelial, neuron/neuron contacts are not necessary for ORN maturation in vitro. We propose herein to use these dissociated cell cultures, in the first half of this grant, to further characterize the stages of olfactory neuronal differentiation. We will analyze anatomical and molecular changes in ORNs with immunocytochemistry, electron microscopy and in situ hybridization, in collaborations with several members of this Program Project Grant (PPG) group. We will characterize stages in the development of ORN odorant responses with the voltage sensitive dye technology and correlate these stages with stages in molecular differentiation. In the second half of this grant, we propose to investigate specific regulatory controls of differentiation stages, again in collaboration with members of the PPG group. In particular, we propose to investigate the hypothesis that neuronal contact between ORNs and olfactory bulb neurons in culture will provide an additional level of trophic support to ORNs, resulting in an increase in the life span of ORNs and greater numbers of mature, olfactory marker, protein-positive ORNs. Then, we will use the dissociated cell cultures to characterize the effects of specific growth factors on neuronal genesis and initial differentiation into neurons. The EGF family of growth factors has been implicated in control of olfactory neurogenesis and the TGFbeta family has been implicated in initial olfactory neuronal differentiation. These studies will provide information on basic mechanisms of neuronal differentiation that will be instructive of the function of the nervous system in general. Furthermore, knowledge gained about the regulation of olfactory neuronal generation and differentiation might be applicable to other neuronal populations where replacement and continual differentiation and maturation of neurons do not occur.

表征的解剖学、分子和功能特性 哺乳动物嗅觉受体分化的不同阶段 神经元（ORN）尚不清楚。此外，鲜为人知的是 关于从一微分调节运动的控制系统 阶段到另一个阶段。 表征 ORN 分化阶段和 识别调节信号，我们开发了分离细胞培养物 新生和成年大鼠鼻细胞系统。在这些文化中，ORN 是 产生并经历初始分化和成熟 （对气味剂的电反应和嗅觉标记的表达 蛋白质）。 这是迄今为止描述的唯一的分离培养系统 这表明 ORN 已经成熟。我们的初步数据显示或 表明 ORN 有几个分化阶段，即 神经发生和分化受到单独的调控控制， 并且特定的球上皮、神经元/神经元接触不是 ORN 体外成熟所必需的。 我们在此建议首先使用这些分离的细胞培养物 这笔拨款的一半，用于进一步表征嗅觉的阶段 神经元分化。我们将从解剖学和分子学角度进行分析 通过免疫细胞化学、电子显微镜和原位观察 ORN 的变化 与该计划的几个成员合作进行杂交 项目资助（PPG）小组。我们将描述发展阶段 ORN 气味反应与电压敏感染料技术和 将这些阶段与分子分化的阶段相关联。 在 在这笔拨款的下半年，我们建议调查具体的监管 再次与成员合作控制分化阶段 PPG集团旗下。特别是，我们建议研究以下假设 培养物中 ORN 和嗅球神经元之间的神经元接触 将为 ORN 提供额外水平的营养支持，从而 ORN 寿命的延长和成熟数量的增加， 嗅觉标记，蛋白质阳性 ORN。 然后，我们将使用 分离的细胞培养物以表征特定生长的影响 神经元发生和初始分化为神经元的因素。这 EGF 生长因子家族与嗅觉的控制有关 神经发生和 TGFbeta 家族参与了最初的 嗅觉神经元分化。这些研究将提供 有关神经元分化基本机制的信息 对神经系统的一般功能有指导意义。 此外，获得有关嗅觉神经元调节的知识 产生和分化可能适用于其他神经元 更替和持续分化的人群 神经元不会成熟。