title: The E3 ligase CUL3/RDX controls centromere maintenance by ubiquitylating and stabilizing CENP-A in a CAL1-dependent manner.
abstract: Centromeres are defined by the presence of the histone H3 variant CENP-A in a subset of centromeric nucleosomes. CENP-A deposition to centromeres depends on a specialized loading factor from yeast to humans that is called CAL1 in Drosophila. Here, we show that CAL1 directly interacts with RDX, an adaptor for CUL3-mediated ubiquitylation. However, CAL1 is not a substrate of the CUL3/RDX ligase but functions as an additional substrate-specifying factor for the CUL3/RDX-mediated ubiquitylation of CENP-A. Remarkably, ubiquitylation of CENP-A by CUL3/RDX does not trigger its degradation but stabilizes CENP-A and CAL1. Loss of RDX leads to a rapid degradation of CAL1 and CENP-A and to massive chromosome segregation defects during development. Essentially, we identified a proteolysis-independent role of ubiquitin conjugation in centromere regulation that is essential for the maintenance of the centromere-defining protein CENP-A and its loading factor CAL1.
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH-Alliance, University of Heidelberg, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
authors.forename: Debora
authors.initials: D
authors.lastname: Bade
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH-Alliance, University of Heidelberg, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
authors.forename: Anne-Laure
authors.initials: AL
authors.lastname: Pauleau
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH-Alliance, University of Heidelberg, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany.
authors.forename: Astrid
authors.initials: A
authors.lastname: Wendler
authors.affiliation: Zentrum für Molekulare Biologie der Universität Heidelberg (ZMBH), DKFZ-ZMBH-Alliance, University of Heidelberg, Im Neuenheimer Feld 282, 69120 Heidelberg, Germany. Electronic address: s.erhardt@zmbh.uni-heidelberg.de.
authors.forename: Sylvia
authors.initials: S
authors.lastname: Erhardt
mesh_terms: D000818:Animals; D015153:Blotting, Western; D002503:Centromere / Q000502:physiology*; D000076247:Centromere Protein A; D044842:Cullin Proteins / Q000502:physiology*; D004268:DNA-Binding Proteins / Q000378:metabolism*; D029721:Drosophila Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D004331:Drosophila melanogaster / Q000196:embryology / Q000235:genetics / Q000378:metabolism*; D005260:Female; D019084:Fluorescent Antibody Technique, Indirect; D018507:Gene Expression Regulation, Developmental; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D006657:Histones / Q000378:metabolism*; D047468:Immunoprecipitation; D047908:Intracellular Signaling Peptides and Proteins / Q000502:physiology*; D008297:Male; D016297:Mutagenesis, Site-Directed; D009154:Mutation; D059748:Proteolysis; D034741:RNA, Small Interfering / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics / Q000378:metabolism; D020798:Two-Hybrid System Techniques; D025801:Ubiquitin / Q000378:metabolism*; D054875:Ubiquitination
chemical_list: C558282:Cal1 protein, Drosophila; D000076247:Centromere Protein A; C427237:Cid protein, Drosophila; C503647:Cul3 protein, Drosophila; D044842:Cullin Proteins; D004268:DNA-Binding Proteins; D029721:Drosophila Proteins; D006657:Histones; D047908:Intracellular Signaling Peptides and Proteins; D034741:RNA, Small Interfering; C511791:Rdx protein, Drosophila; D011993:Recombinant Fusion Proteins; D025801:Ubiquitin; D049452:Green Fluorescent Proteins