CYCLIC GMP PHOSPHODIESTERASES IN PC12 DIFFERENTIATION

说明NGF导致cGMP刺激的环核苷酸的快速丢失 PC12细胞的磷酸二酯酶(PDE2)活性(24小时后下降50% 小时)。长期使用NGF治疗可导致80%以上的减少 在PDE-2活性中。PDE2mRNA不是迅速下降，而是CaM刺激 PDE(PDE1)mRNAs是由NGF分化诱导的。NGF行动促进 假设神经元存活或PC12分化对 DISTINCT的转录水平和翻译后修饰 PDE和调节它们的蛋白质，以降低总的PDE活性 牢房。交感神经分化被进一步假设为转移 环核苷酸代谢从环GMP调节到环GMP 钙调节状态。 本研究的具体目的是：1)PDE1的结构特征 和来自PC12和交感神经元的PDE2cDNA 2)NGF的评估 对PC12和大鼠交感神经节PDE mRNAs和蛋白质的影响 PDE1和PDE2相互作用蛋白的分子鉴定 克隆和免疫化学分析。

DESCRIPTION NGF causes a rapid loss of cGMP-stimulated cyclic nucleotide phosphodiesterase (PDE2) activity in PC12 cells (50% reduction after 24 hours). Longer treatment with NGF results in a greater than 80% reduction in PDE 2 activity. PDE2 mRNA is not rapidly decreased but CaM-stimulated PDE (PDE1) mRNAs are induced by NGF-differentiation. NGF action to promote neuronal survival or PC12 differentiation is hypothesized to have effects on transcription levels and on post - translational modification of distinct PDEs, and proteins regulating them, to decrease the overall PDE activity of the cell. Sympathetic differentiation is further hypothesized to shift cyclic nucleotide metabolism from a cyclic GMP-regulated to a calcium-regulated state. The specific aims of the study are 1) structural characterization of PDE1 and PDE2 cDNAs from PC12 and sympathetic neurons 2) assessment of NGF effects on PC12 and rat sympathetic ganglia PDE mRNAs and proteins and 3) identification of PDE1- and PDE2-interacting proteins through molecular cloning and immunochemical analysis.