Wu Y Y, Bradshaw R A
Department of Biological Chemistry, College of Medicine, University of California, Irvine 92717-1700, USA.
J Cell Physiol. 1995 Sep;164(3):522-32. doi: 10.1002/jcp.1041640310.
A variant cell line, designated E2, characterized by more rapid responses to nerve growth factor (NGF) and basic fibroblast growth factor (bFGF) and markedly more robust responses to interleukin-6 and 8-Br-cAMP, has been subcloned from the rat PC12 cell line. The enhanced responsiveness to NGF in E2 cells is not due to receptor overexpression as judged by TrkA protein levels and tyrosine kinase activity, but may be associated with the increased and prolonged tyrosine phosphorylation of ERK1 (extracellular signal regulated kinase 1) and ERK2. The rapid morphological differentiation induced by different growth factors in E2 cells is mediated in a transcription-independent manner suggesting that E2 cells may constitutively express some differentiation-associated molecules that allow direct entry into the neuronal program.
一种名为E2的变异细胞系已从大鼠PC12细胞系中克隆出来，其特点是对神经生长因子（NGF）和碱性成纤维细胞生长因子（bFGF）的反应更快，对白细胞介素-6和8-溴环磷酸腺苷（8-Br-cAMP）的反应明显更强。根据TrkA蛋白水平和酪氨酸激酶活性判断，E2细胞对NGF反应增强并非由于受体过度表达，而是可能与细胞外信号调节激酶1（ERK1）和ERK2酪氨酸磷酸化增加及延长有关。不同生长因子在E2细胞中诱导的快速形态分化是以不依赖转录的方式介导的，这表明E2细胞可能组成性表达一些与分化相关的分子，从而能够直接进入神经元程序。
