PACAP REGULATION OF NEUROGENESIS AND SURVIVAL

PACAP 对神经发生和生存的调节

• 批准号: 2037735
• 负责人: Emanuel Murray DiCicco-Bloom
• 金额: $ 19.05万
• 依托单位: UNIV OF MED/DENT NJ-R W JOHNSON MED SCH
• 依托单位国家: 美国
• 财政年份: 1994
• 资助国家: 美国
• 起止时间: 1994-01-01 至 1998-12-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/2037735
• 关键词: DNA footprinting; adenylate cyclase; autocrine; autoradiography; cell cycle; cyclic AMP; enzyme activity; gene induction /repression; genetic regulatory element; growth factor receptors; immunocytochemistry; laboratory rat; lipid metabolism; neurogenesis; neurotrophic factors; northern blottings; nucleotide metabolism; phosphatidylinositols; pituitary hormones; protein tyrosine kinase; receptor expression; tissue /cell culture; transcription factor; vasoactive intestinal peptide

While the growth of neuronal population has been well-characterized in vivo, underlying molecular mechanisms remains undefined. The goal of this proposal is to define the role of PACAP (pituitary adenylate cyclase activating peptide) in regulating the three principal mechanisms contributing to neuronal population growth including 1) stimulating mitosis of precursor or neuroblasts, 2) enhancing survival of proliferating precursors and 3) promoting longer-term survival through action of target-derived neurotrophic factor s. PACAP may be critical to normal brain development, since this neuropeptide influences neurogenic and survival of multiple prenatal and postnatal as well as peripheral and central populations. Our specific aim are to define the effects of PACAP on neuroblast mitosis and survival as well as expression of the trk family mRNA's. Second, characterized the effect of PACAP on second messenger systems: cAMP and phosphatidyl inositol (PI) metabolism. Third, define dht regulation and expression of PACAP protein and mRNA in the neurogenetic populations, and characterized peptide autocrine and autoregulatory activity. Fourth, characterized PACAP induction of DNA binding activities that interact with cAMP response elements (CRE's) and other DNA sites in target neuronal gene promoter. Our strategy employs pure populations of mitotic neuroblasts from embryonic sympathetic and sensory ganglia, cerebral cortical neuroepithelium and postnatal cerebellar cortex to identity population- specific and age-dependent PACAP regulation. We examine mitogenic and trophic effects by assaying cell number, [3H]thymidine incorporation, and neurite outgrowth. cAMP and PACAP protein will be assessed y radioimmunoassay an PI metabolism by ion-exchange chromatography. mRNA;s will be assayed by Norther analysis. PACAP induction of population- specific binding activities will be characterized by gel retardation, DNAse I footprinting, and UV crosslinking procedures. By characterizing PACAP actions in peripheral and central neurogenetic populations, we many define mechanisms by which the single peptide, PACAP, differentially regulates population-specific neurogenesis and survival. Hopefully we may learn how extracellular signals, acting via second messenger and transcriptional pathways, alter neuroblast division, survival and trophic factor receptor expression to generate diverse neuronal populations. Insight into second messenger and transcription pathways underlying PACAP mitogenic and trophic activity may identify loci where disease processes intervene to produce dysraphic sates, holoprosencephaly, and systems disorders.

虽然神经元数量的增长已被充分表征 体内，潜在的分子机制仍不清楚。 目标是 该提案旨在定义 PACAP（垂体腺苷酸环化酶）的作用 激活肽）调节三个主要机制 促进神经元数量增长，包括 1) 刺激 前体细胞或神经母细胞的有丝分裂，2) 增强存活率 增殖的前体细胞和 3) 通过以下方式促进长期生存 靶源性神经营养因子 s 的作用。 PACAP 可能至关重要 对正常的大脑发育有影响，因为这种神经肽影响 神经源性和多种产前和产后以及生存 外围和中心人群。 我们的具体目标是确定 PACAP 对神经母细胞有丝分裂的影响 以及 trk 家族 mRNA 的存活和表达。 第二， 表征了 PACAP 对第二信使系统的影响：cAMP 和 磷脂酰肌醇（PI）代谢。 第三，定义 dht 监管和 PACAP 蛋白和 mRNA 在神经发生群体中的表达，以及 表征肽自分泌和自动调节活性。 第四， 表征 PACAP 诱导 DNA 结合活性相互作用 具有 cAMP 反应元件 (CRE) 和目标中的其他 DNA 位点 神经元基因启动子。 我们的策略采用来自有丝分裂神经母细胞的纯群体 胚胎交感神经节和感觉神经节、大脑皮质 神经上皮和出生后小脑皮质来识别人群 特定且与年龄相关的 PACAP 调节。 我们检查促有丝分裂和 通过测定细胞数量、[3H]胸苷掺入以及 神经突生长。 cAMP 和 PACAP 蛋白将进行评估 通过离子交换色谱法进行放射免疫分析 PI 代谢。 mRNA；s 将通过Norther分析进行测定。 PACAP 诱导群体- 特异性结合活性的特征在于凝胶延迟， DNAse I 足迹和 UV 交联程序。 通过表征 PACAP 在外周和中枢神经发生中的作用 人群，我们许多人定义了单肽的机制， PACAP，差异调节群体特异性神经发生和 生存。希望我们可以了解细胞外信号如何通过 第二信使和转录途径，改变神经母细胞分裂， 生存和营养因子受体表达产生不同的 神经元群。 深入了解第二信使和转录 PACAP 有丝分裂和营养活性的潜在途径可能会确定 疾病过程干预产生通气障碍状态的位点， 前脑无裂畸形和系统疾病。