title: The HP1 homolog rhino anchors a nuclear complex that suppresses piRNA precursor splicing.
abstract: piRNAs guide an adaptive genome defense system that silences transposons during germline development. The Drosophila HP1 homolog Rhino is required for germline piRNA production. We show that Rhino binds specifically to the heterochromatic clusters that produce piRNA precursors, and that binding directly correlates with piRNA production. Rhino colocalizes to germline nuclear foci with Rai1/DXO-related protein Cuff and the DEAD box protein UAP56, which are also required for germline piRNA production. RNA sequencing indicates that most cluster transcripts are not spliced and that rhino, cuff, and uap56 mutations increase expression of spliced cluster transcripts over 100-fold. LacI::Rhino fusion protein binding suppresses splicing of a reporter transgene and is sufficient to trigger piRNA production from a trans combination of sense and antisense reporters. We therefore propose that Rhino anchors a nuclear complex that suppresses cluster transcript splicing and speculate that stalled splicing differentiates piRNA precursors from mRNAs.
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, MA 01605, USA; Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester MA 01605, USA.
authors.forename: Zhao
authors.initials: Z
authors.lastname: Zhang
authors.affiliation: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 368 Plantation Street, Worcester MA 01605, USA.
authors.forename: Jie
authors.initials: J
authors.lastname: Wang
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, MA 01605, USA.
authors.forename: Nadine
authors.initials: N
authors.lastname: Schultz
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, MA 01605, USA.
authors.forename: Fan
authors.initials: F
authors.lastname: Zhang
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, MA 01605, USA.
authors.forename: Swapnil S
authors.initials: SS
authors.lastname: Parhad
authors.affiliation: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 368 Plantation Street, Worcester MA 01605, USA.
authors.forename: Shikui
authors.initials: S
authors.lastname: Tu
authors.affiliation: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 368 Plantation Street, Worcester MA 01605, USA.
authors.forename: Thom
authors.initials: T
authors.lastname: Vreven
authors.affiliation: Department of Biochemistry and Molecular Pharmacology, University of Massachusetts Medical School, 364 Plantation Street, Worcester MA 01605, USA; RNA Therapeutics Institute, University of Massachusetts Medical School, 368 Plantation Street, Worcester MA 01605, USA; Howard Hughes Medical Institute.
authors.forename: Phillip D
authors.initials: PD
authors.lastname: Zamore
authors.affiliation: Program in Bioinformatics and Integrative Biology, University of Massachusetts Medical School, 368 Plantation Street, Worcester MA 01605, USA. Electronic address: zhiping.weng@umassmed.edu.
authors.forename: Zhiping
authors.initials: Z
authors.lastname: Weng
authors.affiliation: Program in Molecular Medicine, University of Massachusetts Medical School, 373 Plantation Street, Worcester, MA 01605, USA. Electronic address: william.theurkauf@umassmed.edu.
authors.forename: William E
authors.initials: WE
authors.lastname: Theurkauf
mesh_terms: D000818:Animals; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism*; D053487:DEAD-box RNA Helicases / Q000378:metabolism; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism*; D004331:Drosophila melanogaster / Q000235:genetics / Q000378:metabolism; D005260:Female; D010053:Ovary / Q000378:metabolism; D012326:RNA Splicing; D034741:RNA, Small Interfering / Q000235:genetics* / Q000378:metabolism; D016601:RNA-Binding Proteins / Q000378:metabolism; D055755:SOXD Transcription Factors / Q000235:genetics
chemical_list: D002868:Chromosomal Proteins, Non-Histone; C000590395:Cuff protein, Drosophila; D029721:Drosophila Proteins; D034741:RNA, Small Interfering; D016601:RNA-Binding Proteins; C587040:SOX102F protein, Drosophila; D055755:SOXD Transcription Factors; C449641:rhi protein, Drosophila; C107854:Hel25E protein, Drosophila; D053487:DEAD-box RNA Helicases