Molecular characteristics of the heterochromatic I elements from a reactive strain ofDrosophila melanogaster |
| |
Authors: | C Vaury P Abad A Pelisson A Lenoir A Bucheton |
| |
Institution: | (1) Laboratoire de Génétique, Université Blaise Pascal, 63177 Aubière cédex, France;(2) Centre de Recherche d'Antibes, INRA, BP2078, 06606 Antibes cédex, France;(3) Centre de Génétique Moléculaire, CNRS, 91190 Gif-sur-Yvette, France |
| |
Abstract: | Summary There are two categories of strains inDrosophila melanogaster with respect to the I-R system of hybrid dysgenesis. The inducer strains contain particular transposable elements named I factors. They are not present in the strains of the other category called reactive (R) strains. Defective I elements are present in the pericentromeric regions of both categories of strains. This last subfamily of I sequences has not yet been described in detail and little is known about its origin. In this paper, we report that the defective I elements display an average of 94% of sequence identity with each other and with the transposable I factor. The results suggest that they cannot be the progenitors of the present day I factors, but that each of these two subfamilies started to evolve independently several million years ago. Furthermore, the sequence comparison of these I elements with an active I factor fromDrosophila teissieri provides useful information about when the deleted I elements became immobilized. |
| |
Keywords: | Drosophila melanogaster Evolution Hybrid dysgenesis I elements Transposons |
本文献已被 SpringerLink 等数据库收录! |
|