title: A genome-wide RNAi screen draws a genetic framework for transposon control and primary piRNA biogenesis in Drosophila.
abstract: A large fraction of our genome consists of mobile genetic elements. Governing transposons in germ cells is critically important, and failure to do so compromises genome integrity, leading to sterility. In animals, the piRNA pathway is the key to transposon constraint, yet the precise molecular details of how piRNAs are formed and how the pathway represses mobile elements remain poorly understood. In an effort to identify general requirements for transposon control and components of the piRNA pathway, we carried out a genome-wide RNAi screen in Drosophila ovarian somatic sheet cells. We identified and validated 87 genes necessary for transposon silencing. Among these were several piRNA biogenesis factors. We also found CG3893 (asterix) to be essential for transposon silencing, most likely by contributing to the effector step of transcriptional repression. Asterix loss leads to decreases in H3K9me3 marks on certain transposons but has no effect on piRNA levels.
authors.affiliation: Watson School of Biological Sciences, Howard Hughes Medical Institute, Cold Spring Harbor Laboratory, Cold Spring Harbor, NY 11724, USA.
authors.forename: Felix
authors.initials: F
authors.lastname: Muerdter
authors.forename: Paloma M
authors.initials: PM
authors.lastname: Guzzardo
authors.forename: Jesse
authors.initials: J
authors.lastname: Gillis
authors.forename: Yicheng
authors.initials: Y
authors.lastname: Luo
authors.forename: Yang
authors.initials: Y
authors.lastname: Yu
authors.forename: Caifu
authors.initials: C
authors.lastname: Chen
authors.forename: Richard
authors.initials: R
authors.lastname: Fekete
authors.forename: Gregory J
authors.initials: GJ
authors.lastname: Hannon
mesh_terms: D000818:Animals; D004251:DNA Transposable Elements; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics* / Q000378:metabolism; D005260:Female; D055785:Gene Knockdown Techniques; D020868:Gene Silencing; D049750:Genome, Insect; D010053:Ovary / Q000502:physiology; D034622:RNA Interference; D034741:RNA, Small Interfering / Q000235:genetics / Q000378:metabolism*; D015203:Reproducibility of Results; D025842:SUMO-1 Protein / Q000235:genetics / Q000378:metabolism
chemical_list: C539309:Asl protein, Drosophila; D004251:DNA Transposable Elements; D029721:Drosophila Proteins; D034741:RNA, Small Interfering; D025842:SUMO-1 Protein