CYCLIC GMP PHOSPHODIESTERASES IN PC12 DIFFERENTIATION

描述NGF导致cGMP刺激的环核苷酸快速丢失 PC12细胞中的磷酸二酯酶（PDE 2）活性（24小时后降低50 小时）。 用NGF治疗更长时间可减少80%以上 PDE 2活性。 PDE2 mRNA没有迅速降低，但钙调素刺激 PDE（PDE1）mRNA由NGF分化诱导。 NGF促进 神经元存活或PC12分化被假设对 转录水平和翻译后修饰的不同 PDE和调节它们的蛋白质，以降低 牢房 进一步假设交感神经分化 环核苷酸代谢从环GMP调节到 钙调节状态 本研究的具体目的是：1）PDE 1的结构表征 和PDE2 cDNA 2）评估NGF 对PC12和大鼠交感神经节PDE mRNA和蛋白质的影响，以及3） 通过分子生物学鉴定PDE 1和PDE 2相互作用蛋白 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.