TELOMERE-ASSOCIATED REPEATS IN CHIRONOMUS FORM DISCRETE SUBFAMILIES GENERATED BY GENE CONVERSION
TELOMERE-ASSOCIATED REPEATS IN CHIRONOMUS FORM DISCRETE SUBFAMILIES GENERATED BY GENE CONVERSION
复制标题
DOI：
10.1007/bf00183222
复制
发表时间：
1992-08-01
影响因子：
3.9
通讯作者：
EDSTROM, JE
中科院分区：
文献类型：
--
作者：
COHN, M;EDSTROM, JE
在双翅目昆虫中，已知存在的最远端端粒相关DNA由长而复杂的串联重复序列组成。我们对苍白摇蚊的340 bp串联重复序列进行了分类。重复序列分布在少数的亚家族中。一种类型的重复具有主单元的特征，通常通过简单的改变可以从该主单元导出其他主要单元。衍生的亚家族包含的片段是主序列中相应片段的简并版本。这样的片段也可以以不同的组合一起出现在同一个重复单元中。在位于简并片段之外的区域中完全不存在亚家族特异性碱基变体。均质化发生在通常小于整个重复单元的DNA序列之间。重复序列的镶嵌结构表明，基因转换是产生和维持这个重复序列家族的重要力量。
In dipteran insects the most distal telomere-associated DNA known to exist consists of long, complex tandem repeats. We have classified the 340-bp tandemly arranged repeats in Chironomus pallidivittatus. The repeats are distributed in a small number of subfamilies. One type of the repeat has the character of a master unit from which other main units can be derived usually by simple changes. The derived subfamilies contain segments that are degenerate versions of the corresponding segment in the master sequence. Such segments can also occur together in one and the same repeat unit in different combinations. There is a complete absence of subfamily-specific base variants in regions lying outside of the degenerate segments. Homogenization takes place between DNA sequences that are often smaller than a whole repeat unit. The mosaic structure of the repeat arrays suggests that gene conversion is an important force in the generation and maintenance of this family of repeats.