Amplification and loss of dihydrofolate reductase genes in a Chinese hamster ovary cell line.
Amplification and loss of dihydrofolate reductase genes in a Chinese hamster ovary cell line.
复制标题
中国仓鼠卵巢细胞系中二氢叶酸还原酶基因的扩增和丢失。
DOI：
10.1128/mcb.1.12.1069-1076.1981
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发表时间：
1981
影响因子：
5.3
通讯作者：
Schimke,RT
中科院分区：
文献类型：
--
作者：
Kaufman,RJ;Schimke,RT
在培养基中甲氨蝶呤浓度逐步增加的过程中，我们选择了二氢叶酸还原酶水平升高的中国仓鼠卵巢细胞，该水平与二氢叶酸还原酶基因拷贝数（即基因扩增）成正比。我们使用荧光激活细胞分选技术研究了经历甲氨蝶呤耐药初始步骤的单个细胞中的二氢叶酸还原酶水平。这些细胞构成了具有不同二氢叶酸还原酶水平的异质群体，并且当它们在不存在甲氨蝶呤的情况下生长时，它们特征性地失去了升高的酶水平。具有高酶水平的单个细胞的后代表现不同，并且可能丢失全部或不同数量的扩增基因。
During stepwise increases in the methotrexate concentration in culture medium, we selected Chinese hamster ovary cells that contained elevated dihydrofolate reductase levels which were proportional to the number of dihydrofolate reductase gene copies (i.e., gene amplification). We studied the dihydrofolate reductase levels in individual cells that underwent the initial steps of methotrexate resistance by using the fluorescence-activated cell sorter technique. Such cells constituted a heterogeneous population with differing dihydrofolate reductase levels, and they characteristically lost the elevated enzyme levels when they were grown in the absence of methotrexate. The progeny of individual cells with high enzyme levels behaved differently and could lose all or variable numbers of the amplified genes.