title: Integral nuclear pore proteins bind to Pol III-transcribed genes and are required for Pol III transcript processing in C. elegans.
abstract: Nuclear pores associate with active protein-coding genes in yeast and have been implicated in transcriptional regulation. Here, we show that in addition to transcriptional regulation, key components of C. elegans nuclear pores are required for processing of a subset of small nucleolar RNAs (snoRNAs) and tRNAs transcribed by RNA polymerase (Pol) III. Chromatin immunoprecipitation of NPP-13 and NPP-3, two integral nuclear pore components, and importin-β IMB-1 provides strong evidence that this requirement is direct. All three proteins associate specifically with tRNA and snoRNA genes undergoing Pol III transcription. These pore components bind immediately downstream of the Pol III preinitiation complex but are not required for Pol III recruitment. Instead, NPP-13 is required for cleavage of tRNA and snoRNA precursors into mature RNAs, whereas Pol II transcript processing occurs normally. Our data suggest that integral nuclear pore proteins act to coordinate transcription and processing of Pol III transcripts in C. elegans.
authors.affiliation: Department of Biology, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA; Carolina Center for Genome Sciences, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA.
authors.forename: Kohta
authors.initials: K
authors.lastname: Ikegami
authors.forename: Jason D
authors.initials: JD
authors.lastname: Lieb
mesh_terms: D000818:Animals; D017173:Caenorhabditis elegans / Q000235:genetics*; D029742:Caenorhabditis elegans Proteins / Q000378:metabolism; D028884:Karyopherins / Q000378:metabolism; D022022:Nuclear Pore / Q000235:genetics*; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism; D012320:RNA Polymerase III / Q000235:genetics* / Q000378:metabolism; D020537:RNA, Small Nucleolar / Q000235:genetics / Q000378:metabolism; D012343:RNA, Transfer / Q000235:genetics / Q000378:metabolism; D014158:Transcription, Genetic
chemical_list: D029742:Caenorhabditis elegans Proteins; C475890:IMB-1 protein, C elegans; D028884:Karyopherins; C577012:NPP-3 protein, C elegans; D028861:Nuclear Pore Complex Proteins; D020537:RNA, Small Nucleolar; D012343:RNA, Transfer; D012320:RNA Polymerase III