title: Centromeric localization of dispersed Pol III genes in fission yeast.
abstract: The eukaryotic genome is a complex three-dimensional entity residing in the nucleus. We present evidence that Pol III-transcribed genes such as tRNA and 5S rRNA genes can localize to centromeres and contribute to a global genome organization. Furthermore, we find that ectopic insertion of Pol III genes into a non-Pol III gene locus results in the centromeric localization of the locus. We show that the centromeric localization of Pol III genes is mediated by condensin, which interacts with the Pol III transcription machinery, and that transcription levels of the Pol III genes are negatively correlated with the centromeric localization of Pol III genes. This centromeric localization of Pol III genes initially observed in interphase becomes prominent during mitosis, when chromosomes are condensed. Remarkably, defective mitotic chromosome condensation by a condensin mutation, cut3-477, which reduces the centromeric localization of Pol III genes, is suppressed by a mutation in the sfc3 gene encoding the Pol III transcription factor TFIIIC subunit, sfc3-1. The sfc3-1 mutation promotes the centromeric localization of Pol III genes. Our study suggests there are functional links between the process of the centromeric localization of dispersed Pol III genes, their transcription, and the assembly of condensed mitotic chromosomes.
authors.affiliation: The Wistar Institute, Philadelphia, PA 19104, USA.
authors.forename: Osamu
authors.initials: O
authors.lastname: Iwasaki
authors.forename: Atsunari
authors.initials: A
authors.lastname: Tanaka
authors.forename: Hideki
authors.initials: H
authors.lastname: Tanizawa
authors.forename: Shiv I S
authors.initials: SI
authors.lastname: Grewal
authors.forename: Ken-Ichi
authors.initials: K
authors.lastname: Noma
mesh_terms: D000251:Adenosine Triphosphatases / Q000235:genetics; D018797:Cell Cycle Proteins / Q000378:metabolism; D002467:Cell Nucleus / Q000235:genetics; D002503:Centromere / Q000201:enzymology* / Q000235:genetics*; D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D015825:Chromosomes, Fungal / Q000378:metabolism; D004258:DNA Polymerase III / Q000235:genetics*; D004268:DNA-Binding Proteins / Q000235:genetics; D005800:Genes, Fungal / Q000235:genetics*; D007399:Interphase; D008938:Mitosis; D046912:Multiprotein Complexes / Q000235:genetics; D009154:Mutation / Q000235:genetics; D011485:Protein Binding; D021381:Protein Transport; D012568:Schizosaccharomyces / Q000166:cytology / Q000201:enzymology* / Q000235:genetics*; D029702:Schizosaccharomyces pombe Proteins / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000378:metabolism; D014158:Transcription, Genetic; D000097722:Cohesins
chemical_list: D000251:Adenosine Triphosphatases; D018797:Cell Cycle Proteins; D002868:Chromosomal Proteins, Non-Histone; D004258:DNA Polymerase III; D004268:DNA-Binding Proteins; D046912:Multiprotein Complexes; D029702:Schizosaccharomyces pombe Proteins; D014157:Transcription Factors; D000097722:Cohesins; C108312:condensin complexes