ADAPTIVE REVERSION OF A FRAMESHIFT MUTATION IN ESCHERICHIA-COLI BY SIMPLE BASE DELETIONS IN HOMOPOLYMERIC RUNS
ADAPTIVE REVERSION OF A FRAMESHIFT MUTATION IN ESCHERICHIA-COLI BY SIMPLE BASE DELETIONS IN HOMOPOLYMERIC RUNS
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DOI：
10.1126/science.8023164
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发表时间：
1994-07-15
期刊：
影响因子：
56.9
通讯作者：
TRIMARCHI, JM
中科院分区：
文献类型：
--
作者：
FOSTER, PL;TRIMARCHI, JM
自发突变被认为主要发生在生长的细胞中。然而，在营养缺乏的细胞中也会出现自发突变，在某些情况下，这一过程似乎是适应性的。据报道，当大肠杆菌的Lac（-）菌株接受乳糖使用选择时，产生的Lac（+）突变谱与未经选择产生的突变谱不同，而且更简单。在选择过程中出现的突变主要是一个重复的碱基运行中的碱基缺失。重复DNA元件中发生的类似突变与多种人类遗传性疾病相关，并且在不能纠正异源双链DNA的细胞中增加。
Spontaneous mutations are thought to occur primarily in growing cells. However, spontaneous mutations also arise in nutritionally deprived cells, and in some cases this process appears to be adaptive. Here it is reported that when a Lac(-) strain of Escherichia coli is under selection for lactose use, the spectrum of Lac(+) mutations that arises is different, and simpler, than that arising without selection. Mutations appearing during selection were mainly one-base deletions in runs of iterated bases. Similar mutations occurring in repetitive DNA elements are associated with a variety of human hereditary diseases and are increased in cells that cannot correct heteroduplex DNA.