title: Piwi-interacting RNAs protect DNA against loss during Oxytricha genome rearrangement.
abstract: Genome duality in ciliated protozoa offers a unique system to showcase their epigenome as a model of inheritance. In Oxytricha, the somatic genome is responsible for vegetative growth, whereas the germline contributes DNA to the next sexual generation. Somatic nuclear development removes all transposons and other so-called "junk" DNA, which comprise ~95% of the germline. We demonstrate that Piwi-interacting small RNAs (piRNAs) from the maternal nucleus can specify genomic regions for retention in this process. Oxytricha piRNAs map primarily to the somatic genome, representing the ~5% of the germline that is retained. Furthermore, injection of synthetic piRNAs corresponding to normally deleted regions leads to their retention in later generations. Our findings highlight small RNAs as powerful transgenerational carriers of epigenetic information for genome programming.
authors.affiliation: Department of Molecular Biology, Princeton University, Princeton, NJ 08544, USA.
authors.forename: Wenwen
authors.initials: W
authors.lastname: Fang
authors.forename: Xing
authors.initials: X
authors.lastname: Wang
authors.forename: John R
authors.initials: JR
authors.lastname: Bracht
authors.forename: Mariusz
authors.initials: M
authors.lastname: Nowacki
authors.forename: Laura F
authors.initials: LF
authors.lastname: Landweber
mesh_terms: D000595:Amino Acid Sequence; D001483:Base Sequence; D003227:Conjugation, Genetic; D015321:Gene Rearrangement; D018503:Genome, Protozoan; D048648:Macronucleus / Q000235:genetics; D008969:Molecular Sequence Data; D016813:Oxytricha / Q000166:cytology* / Q000235:genetics*; D010802:Phylogeny; D016053:RNA, Protozoan / Q000235:genetics*; D034741:RNA, Small Interfering / Q000235:genetics*; D016415:Sequence Alignment
chemical_list: D016053:RNA, Protozoan; D034741:RNA, Small Interfering