REGULATION OF NEURONAL MITOSIS

神经元有丝分裂的调节

• 批准号: 6108482
• 负责人: Emanuel Murray DiCicco-Bloom
• 金额: $ 14.52万
• 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: 1999
• 资助国家: 美国
• 起止时间: 1999-04-01 至 2000-03-31
• 项目状态: 已结题
• 来源: https://reporter.nih.gov/project-details/6108482
• 关键词: autoradiography; axon; biological signal transduction; blood brain barrier; brain cell; cell cycle; cell death; cell growth regulation; cell proliferation; cerebellum; cerebrospinal fluid; dendrites; developmental neurobiology; fibroblast growth factor; gene expression; hippocampus; laboratory rat; microscopy; neurogenesis; neuronal transport; olfactory lobe; radioimmunoassay

Our long term goal is to define mechanisms regulating generation of peripheral and central neurons from dividing precursors. Previously, we found that epigenetic factors regulate proliferation in a population- specific fashion, increasing precursor mitosis and survival. While evidence suggests that local factors control neurogenesis, our current studies indicate that distant signals also influence proliferation: 1) Dividing precursors in culture and in vivo possess "paramitotic" neurites, through which target-derived signals alter mitosis and survival; 2) Peripheral injection of bFGF stimulates brain neurogenesis, crossing rapidly the blood-brain barrier (BBB). Thus distant target signals, acting via paramitotic processes or across the BBB, may serve to coordinate body and brain growth. We will define the effects of distant signals in culture and in vivo, examining neurogenesis during ontogeny and maturity. Specifically, we will define (a) axodendritic identity and developmental expression of sympathetic neuroblast paramitotic processes, (b) paramitotic processes and target regulation and expression of cerebellar granule paramitotic processes, (d) kinetics and selectivity of peripheral bFGF transport across the BBB, (e) fate of bFGF-responsive cells in developing and mature brain, and (f) ontogenic and reparative functions of bFGF-induced neurogenesis. Our strategy employs neuronal precursors from embryonic sympathetic ganglia and postnatal brain, including cerebellum, hippocampus, olfactory bulb, and subventricular zone. Mitotic cells are assessed by incorporation of [3H] thymidine and BrdU. Cell survival, neurite outgrowth, and division are assayed by microscopy, retrograde axonal tracing, and time-lapse analysis. Cell death will be assayed by TUNEL and DNA fragmentation. Neural fate and axodendritic characters of mitotic precursors is defined by immuno-colocalization of BrdU and neuroglial antigens. Kinetics of bFGF transport into brain and CSF is detected using spectroscopy of 125I-bFGF and RIA of unlabeled factor. Long term neurogenetic effects of peripheral bFGF will be assessed biochemically and morphologically, during ontogeny and maturity, and after brain damage. By defining target and somatic regulation of proliferation, we may gain insight into mechanisms of normal ontogeny, providing new pathogenetic models. Further, we may design therapies, such as peripheral bFGF, to redress neuronal deficiencies associated with congenital, degenerative, and acquired brain disease.

我们的长期目标是定义调节生成的机制 分裂前体的外围和中央神经元。以前，我们 发现表观遗传因素调节种群中的增殖 - 特定的时尚，越来越多的前体有丝分裂和生存。尽管 有证据表明，局部因素控制神经发生，我们的当前 研究表明，远处信号也会影响增殖：1） 在培养和体内划分的前体具有“优势”神经突， 目标衍生的信号改变了有丝分裂和生存； 2） BFGF的周围注射可刺激脑神经发生，交叉 迅速的血脑屏障（BBB）。因此，遥远的目标信号，行动 通过反质过程或跨BBB，可以用来协调身体 和大脑生长。 我们将定义远处信号在培养和体内的影响， 在本体发育和成熟度期间检查神经发生。具体来说，我们会的 定义（a）轴突齿状身份和发育表达 交感性神经细胞优质过程，（b）优势过程 小脑颗粒的靶向调节和表达 过程，（d）周围BFGF传输的动力学和选择性 在整个BBB中，（e）在发展和成熟的BFGF响应细胞的命运 BFGF诱导的大脑和（F）个体生成和修复功能 神经发生。 我们的策略采用胚胎同情的神经元前体 神经节和产后大脑，包括小脑，海马，嗅觉 灯泡和室内区。通过掺入评估有丝分裂细胞 [3H]胸苷和Brdu的细胞存活，神经突生长和分裂 通过显微镜，逆行轴突示踪和延时来分析 分析。细胞死亡将通过TUNEL和DNA碎片分析。 定义了有丝分裂前体的神经命运和轴突质特征 通过BRDU和神经抗原的免疫定位。 BFGF动力学 使用125i-BFGF的光谱检测到大脑和CSF 和未标记因子的RIA。周围的长期神经遗传学作用 BFGF将在生化和形态学上评估，在个体发育期间 和成熟，脑损伤后。 通过定义目标和躯体调节增殖，我们可能会获得 深入了解正常化的正常机制，提供新的致病性 型号。此外，我们可能会将诸如外围BFGF之类的疗法设计为 与先天性，退化性相关的纠正神经元缺陷 并获得了脑部疾病。