title: Interactions between coilin and PIASy partially link Cajal bodies to PML bodies.
abstract: The eukaryotic nucleus contains a variety of dynamic structures, yet studies into the functional relationship of one type of subnuclear domain to another have been limited. For example, PML bodies and Cajal bodies associate, but the functional consequence of this association and the mediating factors are unknown. Here we report that an associated PML body/Cajal body can co-localize to an snRNA gene locus, with the Cajal body invariably situated between the PML body and the snRNA locus. Binding studies demonstrate that coilin (a Cajal body protein) directly interacts with PIASy (a PML body protein). Cell biological experiments using coilin and PIASy knockout cell lines demonstrate that interactions between coilin and PIASy account in part for the observed association of Cajal bodies with PML bodies. When the PIASy interaction region on coilin is deleted, the frequency of the association between Cajal bodies and PML bodies is reduced. These studies provide another example of coilin's role in the functional organization of the nucleus.
authors.affiliation: Department of Neurology, The University of Mississippi Medical Center, Jackson, MS 39216-4505, USA.
authors.forename: Jun
authors.initials: J
authors.lastname: Sun
authors.forename: Hongzhi
authors.initials: H
authors.lastname: Xu
authors.forename: S H
authors.initials: SH
authors.lastname: Subramony
authors.forename: Michael D
authors.initials: MD
authors.lastname: Hebert
mesh_terms: D002868:Chromosomal Proteins, Non-Histone / Q000378:metabolism; D020541:Coiled Bodies / Q000235:genetics / Q000378:metabolism*; D006367:HeLa Cells; D006801:Humans; D009154:Mutation; D009363:Neoplasm Proteins / Q000235:genetics / Q000378:metabolism*; D009687:Nuclear Proteins / Q000235:genetics / Q000378:metabolism*; D000075223:Poly-ADP-Ribose Binding Proteins; D000071156:Promyelocytic Leukemia Protein; D050828:Protein Inhibitors of Activated STAT / Q000235:genetics / Q000378:metabolism* / Q000502:physiology; D025941:Protein Interaction Mapping; D017413:Ribonucleoprotein, U2 Small Nuclear / Q000235:genetics / Q000378:metabolism; D014157:Transcription Factors / Q000235:genetics / Q000378:metabolism*; D014162:Transfection; D025521:Tumor Suppressor Proteins / Q000235:genetics / Q000378:metabolism*
chemical_list: D002868:Chromosomal Proteins, Non-Histone; D009363:Neoplasm Proteins; D009687:Nuclear Proteins; C485891:PIAS4 protein, human; D000075223:Poly-ADP-Ribose Binding Proteins; D000071156:Promyelocytic Leukemia Protein; D050828:Protein Inhibitors of Activated STAT; D017413:Ribonucleoprotein, U2 Small Nuclear; D014157:Transcription Factors; D025521:Tumor Suppressor Proteins; C047458:fibrillarin; C068921:p80-coilin; C070576:PML protein, human