Increased transmission of mutations by low-condition females: evidence for condition-dependent DNA repair.
Increased transmission of mutations by low-condition females: evidence for condition-dependent DNA repair.
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低条件女性对突变的传播增加：依赖性DNA修复的证据。
DOI：
10.1371/journal.pbio.0060030
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发表时间：
2008-02
期刊：
影响因子：
9.8
通讯作者：
Wang, Alethea D.
中科院分区：
文献类型：
--
作者：
Agrawal, Aneil F.;Wang, Alethea D.
越来越多的证据表明，突变率之高足以使有害等位基因成为影响性别进化、遗传变异维持和许多其他进化现象的主要进化力量。虽然突变率的点估计值正在提高，但我们对个体水平上影响突变率的生物学因素仍然知之甚少。特别重要的是，突变率可能与条件有关，条件低的个体经历更多的突变。理论预测，这种条件依赖性将大大增加种群适应新环境的速度，以及种群遭受突变负荷的程度。尽管它很重要，但在多细胞生物中对这种现象的研究很少。在这里，我们研究了黑腹果蝇的DNA修复过程是否依赖于条件。在这个物种中，精子中受损的DNA可以在受精后通过母体修复过程修复。我们将高条件和低条件的雌性暴露于含有受损DNA的精子中，然后评估这些雌性在父系来源的X染色体上传播的致命突变的频率。低状态雌虫的致死性突变比高状态雌虫高30%，说明低状态雌虫的修复能力降低。另一项单独的实验没有为另一种基于精子选择的假设提供支持。多种进化现象受到突变进入种群的速率以及这些突变在个体之间如何分布的影响。尽管人们通常认为突变在个体中是随机发生的，但事实可能并非如此。如果身体状况不佳的人更容易经历DNA损伤或修复这种损伤的能力较差，那么他们的突变率可能会升高。利用果蝇，我们测试了条件差的个体有效修复诱变剂诱导的DNA损伤的能力是否降低。与预测一致的是，在两个单独的实验中，我们从低条件个体中恢复的突变比从高条件个体中恢复的突变多大约30%。突变率的这种条件依赖性可能导致种群携带比预期更重的有害突变负荷。当雌性果蝇用诱变的精子受精时，如果雌性果蝇处于低而不是高的状态，那么产生的后代携带致命突变的可能性要高30%。
Evidence is mounting that mutation rates are sufficiently high for deleterious alleles to be a major evolutionary force affecting the evolution of sex, the maintenance of genetic variation, and many other evolutionary phenomena. Though point estimates of mutation rates are improving, we remain largely ignorant of the biological factors affecting these rates at the individual level. Of special importance is the possibility that mutation rates are condition-dependent with low-condition individuals experiencing more mutation. Theory predicts that such condition dependence would dramatically increase the rate at which populations adapt to new environments and the extent to which populations suffer from mutation load. Despite its importance, there has been little study of this phenomenon in multicellular organisms. Here, we examine whether DNA repair processes are condition-dependent in Drosophila melanogaster. In this species, damaged DNA in sperm can be repaired by maternal repair processes after fertilization. We exposed high- and low-condition females to sperm containing damaged DNA and then assessed the frequency of lethal mutations on paternally derived X chromosomes transmitted by these females. The rate of lethal mutations transmitted by low-condition females was 30% greater than that of high-condition females, indicating reduced repair capacity of low-condition females. A separate experiment provided no support for an alternative hypothesis based on sperm selection. A variety of evolutionary phenomena are affected by the rate at which mutations enter a population and how those mutations are distributed amongst individuals. Although it is typically assumed that mutations occur randomly among individuals, this may not be the case. Individuals in poor condition may experience elevated mutation rates if they are more prone to experiencing DNA damage or are less able to repair such damage. Using the fruit fly Drosophila melanogaster, we tested whether individuals in poor condition had a reduced capacity to efficiently repair mutagen-induced DNA damage. Consistent with the prediction, we recovered approximately 30% more mutations from low-condition individuals than from high-condition individuals in two separate experiments. Such condition dependence in mutation rate may cause populations to carry considerably heavier loads of deleterious mutations than otherwise expected. When female flies were inseminated with mutagenized sperm, the resulting offspring were 30% more likely to carry a lethal mutation if the female was in low rather than high condition.
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影响因子：
64.8
作者：
Denver, DR;Morris, K;Thomas, WK
通讯作者：
Thomas, WK
DOI：
10.1098/rspb.2000.0976
发表时间：
2000-01-22
影响因子：
4.7
作者：
Goho, S;Bell, G
通讯作者：
Bell, G
DOI：
10.1016/0027-5107(79)90107-6
发表时间：
1979-01-01
期刊：
MUTATION RESEARCH
影响因子：
--
作者：
GRAF, U;GREEN, MM;WURGLER, FE
通讯作者：
WURGLER, FE
影响因子：
3.3
作者：
LANDE, R;SCHEMSKE, DW
通讯作者：
SCHEMSKE, DW
影响因子：
64.8
作者：
Keightley, Peter D.;Otto, Sarah P.
通讯作者：
Otto, Sarah P.