Bucheton A, Vaury C, Chaboissier M C, Abad P, Pélisson A, Simonelig M
Centre de Génétique Moléculaire, CNRS, Gif-sur-Yvette, France.
Genetica. 1992;86(1-3):175-90. doi: 10.1007/BF00133719.
LINEs are a large class of transposable elements in eukaryotes. They transpose by reverse transcription of an RNA intermediate. I elements of Drosophila melanogaster belong to this class and are responsible for the I-R system of hybrid dysgenesis. Many results indicate that at the beginning of the century natural populations of this species were devoid of active I elements and that they were invaded by functional I elements in the last decades. Many Drosophila species contain both defective and active I elements. It seems that the latter were lost in Drosophila melanogaster before its spread throughout the world, and that the recent invasion results from the spread of functional elements originating either from another species by horizontal transfer or from an isolated population of the same species. These data are discussed, as well as their significance in evolutionary processes.
长散在重复序列（LINEs）是真核生物中一大类可转座元件。它们通过RNA中间体的逆转录进行转座。黑腹果蝇的I元件属于此类，是杂种不育I-R系统的原因。许多结果表明，在本世纪初，该物种的自然种群中没有活跃的I元件，而在过去几十年中它们受到了功能性I元件的入侵。许多果蝇物种同时含有缺陷型和活跃型I元件。似乎后者在黑腹果蝇遍布全球之前就已丢失，而最近的入侵是由于功能性元件的传播所致，这些元件要么通过水平转移来自另一个物种，要么来自同一物种的一个孤立种群。本文讨论了这些数据及其在进化过程中的意义。
