Regulatory mechanisms of neuronal differentiation and death by necdin

necdin对神经元分化和死亡的调控机制

基本信息

批准号：
12480230
负责人：
YOSHIKAWA Kazuaki
金额：
$ 10.56万
依托单位：
Osaka University
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (B)
财政年份：
2000
资助国家：
日本
起止时间：
2000 至 2001
项目状态：
已结题

项目摘要

Necdin is expressed in terminally differentiated neurons, and enforced expression of this protein suppresses cell growth. Necdin binds to the transcription factors E2F1 and p53, both of which are involved in neuronal apoptosis, and suppresses their activities. Recently necdin is thought to be a candidate gene for Prader-Willi syndrome, a genomic imprinting-associated neurobehavioral syndrome. Therefore, necdin may be a pivotal factor that controls terminal differentiation and apoptosis in neurons. In this study, we analyzed the molecular interactions between necdin and its target proteins to gain insights into molecular background behind neuronal terminal differentiation and apoptosis. The results obtained are : 1) We isolated two cDNAs encoding proteins that interacts with necdin by yeast two-hybrid assay. One is the cytoplasmic calcium binding protein NEFA, and the other is the nuclear matrix protein hnRNP U. 2) NEFA is localized to the cytoplasm and endoplasmic reticulum, and regulates calcium metabolism in cooperation with necdin. 3) Both necdin and hnRNP U are localized to nuclear matrix and form a complex to suppress cell growth. 4) Necdin is abundant in the cytosol in differentiated neurons. 5) Necdin binds to specific G-rich motif and functions as a transcription repressor. These results suggest that necdin is involved in neuronal terminal differentiation and survival by interacting with various protein present in neuronal nucleus and cytoplasm.

NECDIN在末端分化的神经元中表达，该蛋白质的表达抑制了细胞的生长。 NECDIN与转录因子E2F1和p53结合，这两者都参与神经元凋亡，并抑制其活性。最近，NECDIN被认为是Prader-Willi综合征的候选基因，Prader-Willi综合征是一种基因组印刷相关的神经行为综合征。因此，NECDIN可能是控制神经元中末端分化和凋亡的关键因素。在这项研究中，我们分析了NECDIN及其靶蛋白之间的分子相互作用，以了解神经元末端分化和凋亡背后的分子背景。获得的结果是：1）我们分离了两个编码蛋白质的cDNA，它们通过酵母两杂化测定法与NECDIN相互作用。一种是细胞质钙结合蛋白NEFA，另一个是核基质蛋白HNRNP U. 2）NEFA位于细胞质和内质网中，并调节与Necdin合作中的钙代谢。 3）NECDIN和HNRNP U均位于核基质中，并形成抑制细胞生长的复合物。 4）在分化神经元中的细胞质中，NECDIN丰富。 5）NECDIN与特定的富含G的基序结合，并用作转录阻遏物。这些结果表明，通过与神经元核中存在的各种蛋白质相互作用和细胞质中的各种蛋白质，NECDIN参与了神经元末端分化和存活。