Breakefield X O, Nirenberg M W
Proc Natl Acad Sci U S A. 1974 Jun;71(6):2530-3. doi: 10.1073/pnas.71.6.2530.
A selection procedure was devised for neurons and related cells that depends upon the ability of the cells to synthesize certain amine neurotransmitters. The rationale for selection is that tyrosine is an essential amino acid for most mammalian cells and that three enzymes from mammalian sources can catalyze the synthesis of tyrosine: phenylalanine hydroxylase (EC 1.14.16.1), tyrosine hydroxylase (EC 1.14.16.2), and tryptophan hydroxylase (EC 1.14.16.4). Tyrosine hydroxylase is found predominantly in adrenergic neurons and related cells that synthesize dopamine, norepinephrine, and epinephrine, and tryptophan hydroxylase in cells synthesizing serotonin or melatonin. Only 1 out of 70,000 uncloned mouse neuroblastoma cells grew well in the absence of tyrosine. Approximately 50% of the cell lines obtained by selection had tyrosine hydroxylase activity. This selection procedure thus provides a simple means of obtaining cell lines of neural origin on the basis of their ability to synthesize putative transmitters.
设计了一种针对神经元及相关细胞的筛选程序，该程序取决于细胞合成某些胺类神经递质的能力。筛选的基本原理是，酪氨酸是大多数哺乳动物细胞的必需氨基酸，并且来自哺乳动物的三种酶可以催化酪氨酸的合成：苯丙氨酸羟化酶（EC 1.14.16.1）、酪氨酸羟化酶（EC 1.14.16.2）和色氨酸羟化酶（EC 1.14.16.4）。酪氨酸羟化酶主要存在于合成多巴胺、去甲肾上腺素和肾上腺素的肾上腺素能神经元及相关细胞中，而色氨酸羟化酶存在于合成5-羟色胺或褪黑素的细胞中。在70000个未克隆的小鼠神经母细胞瘤细胞中，只有1个在没有酪氨酸的情况下生长良好。通过筛选获得的细胞系中约50%具有酪氨酸羟化酶活性。因此，这种筛选程序提供了一种基于细胞合成假定递质的能力来获得神经源性细胞系的简单方法。
