POPULATION-GENETICS OF TRANSPOSABLE DNA ELEMENTS - A DROSOPHILA POINT-OF-VIEW
POPULATION-GENETICS OF TRANSPOSABLE DNA ELEMENTS - A DROSOPHILA POINT-OF-VIEW
复制标题
DOI：
10.1007/bf00133712
复制
发表时间：
1992-01-01
期刊：
影响因子：
1.5
通讯作者：
BIEMONT, C
中科院分区：
文献类型：
--
作者：
BIEMONT, C
本文试图汇集各种，分散的数据发表在文献中的插入多态性的转座因子从各种人群（自然群体，实验室菌株，同雌和近交系）。虽然这些结果主要涉及果蝇，但在必要时也纳入了其他生物的数据以说明讨论。相关的数据插入区域，转座和切除率，拷贝数的调节，杂合性的程度进行了分析，以面对与各种理论模型的转座因子的群体生物学的推测。这些模型的参数对转座因子特征值的估计值非常敏感，并且根据这些估计的困难，（群体不平衡，用于估计转座和切除率的特定突变，用于定位插入的原位技术的麻烦，杂交中不期望的TE移动，自发基因组重置，环境影响等）不能准确地决定哪种模型更好地解释这些TE的种群动态。然而，在果蝇中出现的趋势：copia元件显示X染色体上插入缺陷的证据，这一结果与针对copia插入的突变效应的选择一致; P元件再分配没有显着偏离中性假设，尽管X染色体上的插入系统拷贝数高于常染色体上的插入。关于其他元素的数据支持TE遏制的中性模型，两个模型都不支持，或两者都支持。因此，在处理这类数据时，谨慎是必要的。最后讨论了TEs在种群适应和进化中的潜在作用。
This paper is an attempt to bring together the various, dispersed data published in the literature on insertion polymorphism of transposable elements from various kinds of populations (natural populations, laboratory strains, isofemale and inbred lines). Although the results deal mainly with Drosophila, data oil other organisms have been incorporated when necessary to illustrate the discussion. The data pertinent to the regions of insertion, the rates of transposition and excision, the copy number regulation, and the degree of heterozygosity were analysed in order to be confronted with the speculations made with various theoretical models of population biology of transposable elements. The parameters of these models are very sensitive to the values of the transposable element characteristics estimated on populations, and according to the difficulties of these estimations (population not at equilibrium, particular mutations used to estimate the transposition and excision rates, trouble with the in situ technique used to localize the insertions, undesired mobilization of TEs in crosses, spontaneous genome resetting, environmental effects, etc.) it cannot be decided accurately which model better accounts for the population dynamics of these TEs. Tendencies, however, emerge in Drosophila: the copia element shows evidence for deficiency of insertions on the X chromosomes, a result consistent with selection against mutational effects of copia insertions; the P element repartition does not significantly deviate from the neutral assumption, in spite of a systematic copy number of insertions higher on the X than on the autosomes. Data on other elements support either the neutral model of TE containment, neither of the two models, or both. Prudence in conclusion should then be de rigueur when dealing with such kind of data. Finally the potential roles of TEs in population adaptation and evolution are discussed.