期刊
GENETICS
卷 171, 期 4, 页码 1837-1846出版社
GENETICS SOCIETY AMERICA
DOI: 10.1534/genetics.105.047670
关键词
-
Non-LTR retrotransposons R1 and R2 have persisted in rRNA gene loci (rDNA) since the origin of arthropods despite their continued elimination by the recombinational mechanisms of concerted evolution. This study evaluated the short-term evolutionary dynamics of the rDNA locus by measuring the divergence among replicate Drosophila melanogaster lines after 400 generations. The total number of rDNA units on the X chromosome of each line varied from 140 to 310, while the fraction of units inserted with R1 and R2 retrotransposons ranged front 37 to 65%. This level of variation is comparable to that found in natural population surveys. Variation in locus size and retrotransposon load was correlated with large changes in the number of uninserted and R1-inserted units, yet the numbers of R2-inserted units were relatively unchanged. Intergenic spacer (IGS) region length variants were also used to evaluate changes in the rDNA loci. All IGS length variants present in the lines showed significant increases and decreases of copy number. These studies, combined with previous data following specific R1 and R2 insertions in these lines, help to define the type and distribution, both within the locus and within the individual units, of recombinational events that give rise to the concerted evolution of the rDNA loci-is.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据