title: Adaptation to P element transposon invasion in Drosophila melanogaster.
abstract: Transposons evolve rapidly and can mobilize and trigger genetic instability. Piwi-interacting RNAs (piRNAs) silence these genome pathogens, but it is unclear how the piRNA pathway adapts to invasion of new transposons. In Drosophila, piRNAs are encoded by heterochromatic clusters and maternally deposited in the embryo. Paternally inherited P element transposons thus escape silencing and trigger a hybrid sterility syndrome termed P-M hybrid dysgenesis. We show that P-M hybrid dysgenesis activates both P elements and resident transposons and disrupts the piRNA biogenesis machinery. As dysgenic hybrids age, however, fertility is restored, P elements are silenced, and P element piRNAs are produced de novo. In addition, the piRNA biogenesis machinery assembles, and resident elements are silenced. Significantly, resident transposons insert into piRNA clusters, and these new insertions are transmitted to progeny, produce novel piRNAs, and are associated with reduced transposition. P element invasion thus triggers heritable changes in genome structure that appear to enhance transposon silencing.
authors.affiliation: Program in Cell and Developmental Dynamics, University of Massachusetts Medical School, Worcester, MA 01655, USA.
authors.forename: Jaspreet S
authors.initials: JS
authors.lastname: Khurana
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.forename: Jia
authors.initials: J
authors.lastname: Xu
authors.forename: Birgit S
authors.initials: BS
authors.lastname: Koppetsch
authors.forename: Travis C
authors.initials: TC
authors.lastname: Thomson
authors.forename: Anetta
authors.initials: A
authors.lastname: Nowosielska
authors.forename: Chengjian
authors.initials: C
authors.lastname: Li
authors.forename: Phillip D
authors.initials: PD
authors.lastname: Zamore
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Weng
authors.forename: William E
authors.initials: WE
authors.lastname: Theurkauf
mesh_terms: D000818:Animals; D004251:DNA Transposable Elements; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D019143:Evolution, Molecular; D005260:Female; D020868:Gene Silencing; D008297:Male; D010053:Ovary / Q000378:metabolism; D034741:RNA, Small Interfering / Q000378:metabolism
chemical_list: D004251:DNA Transposable Elements; D034741:RNA, Small Interfering