NEUROGENESIS IN THE OLFACTORY AND VOMERONASAL SYSTEMS

这项研究的长期目标是了解这些因素 控制嗅觉神经发生和细胞分化 和犁鼻（VNS）系统。 这两个主要的鼻腔化学感受器 在大多数陆生脊椎动物中发现的系统是唯一的感觉系统， 已知的直接向端脑发送信息的系统， 它们是通过完全不同的途径来实现的。 嗅觉（OE）和 哺乳动物和爬行动物的犁鼻（VNE）上皮在以下方面相似： 都含有双极神经元，在成年期转换， 目标特异性再生后，其各自 神经 因此，哺乳动物和爬行动物的OE和VNE已被使用 成功地在研究出生后的神经发生和比较 再生和发展。 蛇是一种宝贵的研究资源 用于研究OS和VNS的发育过程。 胚胎 蛇可以在养殖场中生长，便于实验操作。 OS和VNS结构通过端脑肥大， 介导了各种各样的蛇的行为。 最后，我希望能研究 细胞分化的后果，OS和VNS，对新生儿和 胚胎行为 本研究的具体目标是：1）识别茎 蛇的OS和VNS中的细胞，使用细胞周期事件的标记， 2)以确定正常发育过程中神经元前体的命运 （3）确定表皮细胞的时空分布 (EGF)神经生长因子受体及其相互关系 fos在蛇的OS和VNS结构中的表达。 使用 免疫细胞化学（ICC）和3 H-胸苷放射自显影（ARG）， 第一个目标是建立一种识别方法， 在OS和VNS结构中的干细胞。 我会决定如何 如果神经元前体的数量在发育过程中发生变化， OS和VNS的受体上皮和端脑结构。 通过用细胞周期标记物和3 H-胸苷ARG双标记细胞， 细胞周期标志物表达和DNA合成之间的相关性将 检查过程中掺入3 H-胸苷的细胞的命运 通过增加3 H-胸苷后的存活时间， 给药至体外生长的胚胎和新生儿中。 国 将使用具有抗体的ICC和原位杂交来评估分化的程度。 用cDNA探针与神经元发育标记物杂交（ISH） 和成熟。 这些研究将建立神经元的时间过程， OS和VNS结构的分化。 第三个目标将决定 OS和VNS结构是否表达EGF和NGF受体，并确定 它们的时间表达与分化期相关。 的 即早基因fos的表达与细胞凋亡相关， 生长因子受体的出现。 这项研究计划的结果 应该阐明细胞周期控制和生长因子如何影响 神经元前体的分化和成熟。

The long-term objective of this research is to understand the factors controlling neurogenesis and cell differentiation in the olfactory (OS) and vomeronasal (VNS) systems. These two major nasal chemosensory systems, found in most terrestrial vertebrates, are the only sensory systems that are known to send information directly to the telencephalon, and they do so via completely separate pathways. The olfactory (OE) and vomeronasal (VNE) epithelia of both mammals and reptiles are similar in that both contain bipolar neurons that turnover during adulthood and show target-specific regeneration following section of their respective nerves. Thus, the OE and VNE of mammals and reptiles have been used successfully in studies of postnatal neurogenesis and comparisons between regeneration and development. Snakes are a valuable research resource for investigating developmental processes in the OS and VNS. Embryonic snakes can be grown in culture, facilitating experimental manipulations. OS and VNS structures are hypertrophied through the telencephalon and mediate a wide variety of snake behaviors. Ultimately, I hope to examine the consequences of cell differentiation, the OS and VNS, on neonatal and embryonic behavior. The specific aims of this research proposal are: 1) to identify stem cells in the OS and VNS of snakes, using markers for cell cycle events, 2) to determine the fate of neuronal precursors during normal development and 3) to identify the spatial and temporal distributions of epidermal (EGF) and neuronal (NGF) growth factor receptors and their relationship to fos expression in OS and VNS structures of snakes. Using immunocytochemistry (ICC) and 3H-thymidine autoradiography (ARG), the purpose of the first aim is to establish a method for identifying reliably stem cells within OS and VNS structures. I will determine how and if the number of neuronal precursors changes during development of the receptor epithelia and telencephalic structures of the OS and VNS. By double labelling cells with cell cycle markers and 3H-thymidine ARG, correlations between cell cycle marker expression and DNA synthesis will examine the fate of cells incorporating 3H-thymidine during the course of normal development by increasing survival times after 3H-thymidine administration into embryos grown in vitro and into neonates. The state of differentiation will be assessed using ICC with antibodies and in situ hybridization (ISH) with cDNA probes to markers for neuronal development and maturation. These studies will establish the time course of neuronal differentiation in OS and VNS structures. The third aim will determine if OS and VNS structures express EGF and NGF receptors and determine if their temporal expression correlates to periods of differentiation. The expression of the immediate-early gene, fos, will be correlated to the appearance of growth factor receptors. The results of this research plan should shed light on how cell cycle control and growth factors influence the differentiation and maturation of neuronal precursors.