Altered gene expression in neurons during programmed cell death: identification of c-jun as necessary for neuronal apoptosis.
Altered gene expression in neurons during programmed cell death: identification of c-jun as necessary for neuronal apoptosis.
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DOI：
10.1083/jcb.127.6.1717
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发表时间：
1994-12
期刊：
影响因子：
--
通讯作者：
Johnson EM Jr
中科院分区：
文献类型：
--
作者：
Estus S;Zaks WJ;Freeman RS;Gruda M;Bravo R;Johnson EM Jr
我们已经研究了神经元程序性细胞死亡需要遗传程序的假设，我们使用了一个模型，其中大鼠交感神经元维持在体外被剥夺了神经生长因子，随后进行细胞凋亡。为了评估这个过程中可能需要的基因表达，我们使用了基于PCR的技术和原位杂交;在NGF剥夺的神经元中鉴定了一般基因抑制和选择性基因诱导的模式。诱导基因的时间级联包括“立即早期基因”，这是显着的，因为它们的诱导发生在最初的刺激神经生长因子去除和一些需要进行蛋白质合成的合成后几个小时。级联反应还包括细胞周期基因c-myb和编码细胞外基质蛋白酶transin和胶原酶的基因。同时原位杂交和核染色显示，虽然c-jun诱导在大多数神经元，c-fos诱导仅限于神经元进行染色质凝聚，凋亡的标志。为了评估由这些基因编码的蛋白质的功能作用，将中和抗体注射到神经元中。针对c-Jun或Fos家族（c-Fos、Fos B、Fra-1和Fra-2）的特异性抗体可以保护缺乏NGF的神经元免受细胞凋亡，而针对Jun B、Jun D或三种非免疫抗体的特异性抗体制备物没有保护作用。由于这些诱导基因编码的蛋白质范围从死亡所必需的转录因子到可能与死亡同时发生的组织重塑有关的蛋白酶，因此这些数据可能概述了负责神经元程序性细胞死亡的遗传程序。
We have examined the hypothesis that neuronal programmed cell death requires a genetic program; we used a model wherein rat sympathetic neurons maintained in vitro are deprived of NGF and subsequently undergo apoptosis. To evaluate gene expression potentially necessary for this process, we used a PCR-based technique and in situ hybridization; patterns of general gene repression and selective gene induction were identified in NGF-deprived neurons. A temporal cascade of induced genes included "immediate early genes," which were remarkable in that their induction occurred hours after the initial stimulus of NGF removal and the synthesis of some required ongoing protein synthesis. The cascade also included the cell cycle gene c-myb and the genes encoding the extracellular matrix proteases transin and collagenase. Concurrent in situ hybridization and nuclear staining revealed that while c-jun was induced in most neurons, c-fos induction was restricted to neurons undergoing chromatin condensation, a hallmark of apoptosis. To evaluate the functional role of the proteins encoded by these genes, neutralizing antibodies were injected into neurons. Antibodies specific for either c-Jun or the Fos family (c-Fos, Fos B, Fra-1, and Fra-2) protected NGF-deprived neurons from apoptosis, whereas antibodies specific for Jun B, Jun D, or three nonimmune antibody preparations had no protective effect. Because these induced genes encode proteins ranging from a transcription factor necessary for death to proteases likely involved in tissue remodeling concurrent with death, these data may outline a genetic program responsible for neuronal programmed cell death.