Impact of multiple insertions of two retroelements, ZAM and Idefix at an euchromatic locus

Citation
C. Conte et al., Impact of multiple insertions of two retroelements, ZAM and Idefix at an euchromatic locus, GENETICA, 109(1-2), 2000, pp. 53-59
Citations number
24
Categorie Soggetti
Molecular Biology & Genetics
Journal title
GENETICA
ISSN journal
00166707 → ACNP
Volume
109
Issue
1-2
Year of publication
2000
Pages
53 - 59
Database
ISI
SICI code
0016-6707(2000)109:1-2<53:IOMIOT>2.0.ZU;2-8
Abstract
Transposable elements represent a large fraction of eukaryotic genomes and they are thought to play an important role in chromatin structure. ZAM and Idefix are two LTR-retrotransposons from Drosophila melanogaster very simil ar in structure to vertebrate retroviruses. In all the strains where their distribution has been studied, ZAM appears to be present exclusively in the intercalary heterochromatin while Idefix copies are mainly found in the ce ntromeric heterochromatin with very few copies in euchromatin. Their distri bution varies in a specific strain called RevI in which the mobilization of ZAM and Idefix is highly induced. In this strain, 15 copies of ZAM and 30 copies of Idefix are found on the chromosomal arms in addition to their usu al distribution. Amongst the loci where new copies are detected, a hotspot for their insertion has been detected at the white locus where up to four e lements occurred within a 3-kb fragment at the 5' end of this gene. This pr operty of ZAM and Idefix to accumulate at a defined site provides an intere sting paradigm to bring insight into the effect exerted by multiple inserti ons of transposable elements at an euchromatic locus.