The rosy region of Drosophila melanogaster and Drosophila simulans. I. Contrasting levels of naturally occurring DNA restriction map variation and divergence.
The rosy region of Drosophila melanogaster and Drosophila simulans. I. Contrasting levels of naturally occurring DNA restriction map variation and divergence.
复制标题
果蝇和模拟果蝇的玫瑰色区域。
DOI：
10.1093/genetics/119.4.875
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发表时间：
1988
期刊：
影响因子：
3.3
通讯作者：
Noon,WA
中科院分区：
文献类型：
--
作者：
Aquadro,CF;Lado,KM;Noon,WA
在北卡罗来纳州的罗利的一个单一地点收集了60个黑腹果蝇品系和30个拟果蝇品系，分析了玫瑰色和蛇位点周围40 kb区域的限制性内切酶图谱变异。DNA序列变异在D. simulans比D.黑腹鱼（每个核苷酸的杂合性为1.9%对0.3%）。这一结果与表型变异研究结果形成鲜明对比，表型变异包括蛋白质（等位酶）、形态和染色体排列，这些表型变异通常较少，地理分化较小。simulans。种内多态性在40-kb区域上不是均匀分布的。每个核苷酸的杂合性水平在D. simulans，高于hsc 2基因。类似地，尽管不那么极端，在D中也观察到杂合性的变化。黑腹菌平均种间差异（种内多态性校正）平均为3.8%。在40 kb区域的种间分歧的模式显示了一些差异与种内变异的空间分布，但一般是一致的选择性中性预测：物种内的多态性最强的区域通常是最分歧的物种之间。序列长度多态性在D.黑腹果蝇的基因水平与该物种的其他基因区域相当。与此相反，没有观察到序列长度的变化之间的D。simulans染色体（分辨率极限约为100 bp）。这些数据表明转座因子在D. simulans与D.黑腹果蝇我们假设，物种有效人口规模的差异是主要的决定因素的对比水平和模式的DNA序列和插入/缺失的变化，我们在这里报告和模式的等位酶和形态变异和分化的其他工人报告这两个物种。
A 40-kb region around the rosy and snake loci was analyzed for restriction map variation among 60 lines of Drosophila melanogaster and 30 lines of Drosophila simulans collected together at a single locality in Raleigh, North Carolina. DNA sequence variation in D. simulans was estimated to be 6.3 times greater than in D. melanogaster (heterozygosities per nucleotide of 1.9% vs. 0.3%). This result stands in marked contrast to results of studies of phenotypic variation including proteins (allozymes), morphology and chromosome arrangements which are generally less variable and less geographically differentiated in D. simulans. Intraspecific polymorphism is not distributed uniformly over the 40-kb region. The level of heterozygosity per nucleotide varies more than 12-fold across the region in D. simulans, being highest over the hsc2 gene. Similar, though less extreme, variation in heterozygosity is also observed in D. melanogaster. Average interspecific divergence (corrected for intraspecific polymorphism) averaged 3.8%. The pattern of interspecific divergence over the 40-kb region shows some disparities with the spatial distribution of intraspecific variation, but is generally consistent with selective neutrality predictions: the most polymorphic regions within species are generally the most divergent between species. Sequence-length polymorphism is observed for D. melanogaster to be at levels comparable to other gene regions in this species. In contrast, no sequence length variation was observed among D. simulans chromosomes (limit of resolution approximately 100 bp). These data indicate that transposable elements play at best a minor role in the generation of naturally occurring genetic variation in D. simulans compared to D. melanogaster. We hypothesize that differences in species effective population size are the major determinant of the contrasting levels and patterns of DNA sequence and insertion/deletion variation that we report here and the patterns of allozyme and morphological variation and differentiation reported by other workers for these two species.