Ferrer I, Olive M, Ribera J, Planas A M
Unitat de Neuropatalogia, Servei d'Anatomia Patològica, Hospital Princeps d'Espanya, Universitat de Barcelona, 08907 Hospitalet de Llobregat, Spain.
Eur J Neurosci. 1996 Jun;8(6):1286-98. doi: 10.1111/j.1460-9568.1996.tb01297.x.
Expression of the different members of transcription factors Fos and Jun was examined in the developing rat brain. Constitutive expression of c-Fos, Fos-related antigens, Jun B and Jun D, as revealed with immunohistochemistry, is higher and more widely distributed in the developing rat brain than in the adult. Selective strong c-Jun expression is observed in the cytoplasm and nuclei of apoptotic cells during the whole process of naturally occurring (programmed) cell death. Cells expressing strong c-Jun immunoreactivity are undetermined cells, neurons and astrocytes. Selective c-Jun expression is also observed following ionizing radiation in rats aged 3 days. Induction of c-jun mRNA, as revealed with in situ hybridization, occurs between 5 and 15 min following gamma-irradiation. Strong c-Jun protein expression appears at 2 h, peaks at 6 h and decreases thereafter to reach normal levels 48 h after gamma-ray exposure. Strong c-Jun protein expression is coincidental with endonuclease activation, as revealed with the method of in situ labelling of nuclear DNA fragmentation, and is restricted to apoptotic cells. Cycloheximide injection at the time of irradiation blocks c-Jun expression, indicating that c-Jun immunoreactivity is attributable to de novo protein synthesis. These observations demonstrate in vivo selective strong c-Jun expression associated with programmed cell death and ionizing radiation-induced apoptosis in the developing rat brain.
在发育中的大鼠脑中检测了转录因子Fos和Jun不同成员的表达。免疫组织化学显示，与成年大鼠脑相比，c-Fos、Fos相关抗原、Jun B和Jun D在发育中的大鼠脑中的组成性表达更高且分布更广。在自然发生（程序性）细胞死亡的整个过程中，在凋亡细胞的细胞质和细胞核中观察到选择性的强c-Jun表达。表达强c-Jun免疫反应性的细胞包括未分化细胞、神经元和星形胶质细胞。在3日龄大鼠接受电离辐射后也观察到选择性的c-Jun表达。原位杂交显示，c-jun mRNA在γ射线照射后5至15分钟之间诱导产生。强c-Jun蛋白表达在2小时出现，6小时达到峰值，此后下降，在γ射线照射后48小时恢复到正常水平。如核DNA片段原位标记法所示，强c-Jun蛋白表达与核酸内切酶激活同时发生，且仅限于凋亡细胞。照射时注射环己酰亚胺可阻断c-Jun表达，表明c-Jun免疫反应性归因于从头合成的蛋白质。这些观察结果证明，在发育中的大鼠脑中，体内选择性强c-Jun表达与程序性细胞死亡和电离辐射诱导的凋亡相关。
