title: A role for the nucleoporin Nup170p in chromatin structure and gene silencing.
abstract: Embedded in the nuclear envelope, nuclear pore complexes (NPCs) not only regulate nuclear transport but also interface with transcriptionally active euchromatin, largely silenced heterochromatin, as well as the boundaries between these regions. It is unclear what functional role NPCs play in establishing or maintaining these distinct chromatin domains. We report that the yeast NPC protein Nup170p interacts with regions of the genome that contain ribosomal protein and subtelomeric genes, where it functions in nucleosome positioning and as a repressor of transcription. We show that the role of Nup170p in subtelomeric gene silencing is linked to its association with the RSC chromatin-remodeling complex and the silencing factor Sir4p, and that the binding of Nup170p and Sir4p to subtelomeric chromatin is cooperative and necessary for the association of telomeres with the nuclear envelope. Our results establish the NPC as an active participant in silencing and the formation of peripheral heterochromatin.
authors: Department of Cell Biology, University of Alberta, Edmonton, Alberta T6G 2H7, Canada.
authors: David W
authors: DW
authors: Van de Vosse
authors: Yakun
authors: Y
authors: Wan
authors: Diego L
authors: DL
authors: Lapetina
authors: Wei-Ming
authors: WM
authors: Chen
authors: Jung-Hsien
authors: JH
authors: Chiang
authors: John D
authors: JD
authors: Aitchison
authors: Richard W
authors: RW
authors: Wozniak
mesh_terms: D002843:Chromatin / Q000737:chemistry / Q000378:metabolism; D004247:DNA / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000378:metabolism; D020868:Gene Silencing; D028861:Nuclear Pore Complex Proteins / Q000378:metabolism*; D009707:Nucleosomes / Q000378:metabolism; D012269:Ribosomal Proteins / Q000235:genetics; D012441:Saccharomyces cerevisiae / Q000235:genetics*; D029701:Saccharomyces cerevisiae Proteins / Q000378:metabolism*; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae / Q000378:metabolism; D016615:Telomere / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism
chemical_list: D002843:Chromatin; D004268:DNA-Binding Proteins; C097178:NUP170 protein, S cerevisiae; D028861:Nuclear Pore Complex Proteins; D009707:Nucleosomes; C103337:RSC complex, S cerevisiae; D012269:Ribosomal Proteins; C061573:SIR4 protein, S cerevisiae; D029701:Saccharomyces cerevisiae Proteins; D038281:Silent Information Regulator Proteins, Saccharomyces cerevisiae; D014157:Transcription Factors; D004247:DNA