title: Suppressor of sable [Su(s)] and Wdr82 down-regulate RNA from heat-shock-inducible repetitive elements by a mechanism that involves transcription termination.
abstract: Although RNA polymerase II (Pol II) productively transcribes very long genes in vivo, transcription through extragenic sequences often terminates in the promoter-proximal region and the nascent RNA is degraded. Mechanisms that induce early termination and RNA degradation are not well understood in multicellular organisms. Here, we present evidence that the suppressor of sable [su(s)] regulatory pathway of Drosophila melanogaster plays a role in this process. We previously showed that Su(s) promotes exosome-mediated degradation of transcripts from endogenous repeated elements at an Hsp70 locus (Hsp70-αβ elements). In this report, we identify Wdr82 as a component of this process and show that it works with Su(s) to inhibit Pol II elongation through Hsp70-αβ elements. Furthermore, we show that the unstable transcripts produced during this process are polyadenylated at heterogeneous sites that lack canonical polyadenylation signals. We define two distinct regions that mediate this regulation. These results indicate that the Su(s) pathway promotes RNA degradation and transcription termination through a novel mechanism.
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA.
authors.forename: Paul
authors.initials: P
authors.lastname: Brewer-Jensen
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA.
authors.forename: Carrie B
authors.initials: CB
authors.lastname: Wilson
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA.
authors.forename: John
authors.initials: J
authors.lastname: Abernethy
authors.affiliation: Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA.
authors.forename: Lonna
authors.initials: L
authors.lastname: Mollison
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA.
authors.forename: Samantha
authors.initials: S
authors.lastname: Card
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA Curriculum in Genetics and Molecular Biology, University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599-3280, USA lsearles@email.unc.edu.
authors.forename: Lillie L
authors.initials: LL
authors.lastname: Searles
mesh_terms: D000818:Animals; D001483:Base Sequence; D002478:Cells, Cultured; D015536:Down-Regulation; D029721:Drosophila Proteins / Q000235:genetics*; D004331:Drosophila melanogaster; D018840:HSP70 Heat-Shock Proteins / Q000235:genetics*; D008969:Molecular Sequence Data; D012313:RNA / Q000235:genetics*; D016601:RNA-Binding Proteins / Q000235:genetics*; D012091:Repetitive Sequences, Nucleic Acid; D020079:Terminal Repeat Sequences; D013728:Terminator Regions, Genetic; D014158:Transcription, Genetic
chemical_list: D029721:Drosophila Proteins; D018840:HSP70 Heat-Shock Proteins; D016601:RNA-Binding Proteins; C416345:su(sable) protein, Drosophila; D012313:RNA
keywords: Dis3; Su(s); Wdr82; noncanonical polyadenylation; nuclear exosome; transcription termination