title: Feedback control of chromosome separation by a midzone Aurora B gradient.
abstract: Accurate chromosome segregation during mitosis requires the physical separation of sister chromatids before nuclear envelope reassembly (NER). However, how these two processes are coordinated remains unknown. Here, we identified a conserved feedback control mechanism that delays chromosome decondensation and NER in response to incomplete chromosome separation during anaphase. A midzone-associated Aurora B gradient was found to monitor chromosome position along the division axis and to prevent premature chromosome decondensation by retaining Condensin I. PP1/PP2A phosphatases counteracted this gradient and promoted chromosome decondensation and NER. Thus, an Aurora B gradient appears to mediate a surveillance mechanism that prevents chromosome decondensation and NER until effective separation of sister chromatids is achieved. This allows the correction and reintegration of lagging chromosomes in the main nuclei before completion of NER.
authors.affiliation: Chromosome Instability and Dynamics Laboratory, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
authors.forename: Olga
authors.initials: O
authors.lastname: Afonso
authors.affiliation: Chromosome Instability and Dynamics Laboratory, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
authors.forename: Irina
authors.initials: I
authors.lastname: Matos
authors.affiliation: Chromosome Instability and Dynamics Laboratory, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.
authors.forename: António J
authors.initials: AJ
authors.lastname: Pereira
authors.affiliation: Chromosome Instability and Dynamics Laboratory, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.|Center for Mathematics, Universidade do Porto, Rua do Campo Alegre 687, 4169-007 Porto, Portugal.
authors.forename: Paulo
authors.initials: P
authors.lastname: Aguiar
authors.affiliation: Department of Biology, University of Pennsylvania, Philadelphia, PA 19104, USA.
authors.forename: Michael A
authors.initials: MA
authors.lastname: Lampson
authors.affiliation: Chromosome Instability and Dynamics Laboratory, Instituto de Biologia Molecular e Celular, Universidade do Porto, Rua do Campo Alegre 823, 4150-180 Porto, Portugal.|Cell Division Unit, Department of Experimental Biology, Faculdade de Medicina, Universidade do Porto, Alameda Prof. Hernâni Monteiro, 4200-319 Porto, Portugal.
authors.forename: Helder
authors.initials: H
authors.lastname: Maiato
mesh_terms: D000705:Anaphase; D000818:Animals; D064107:Aurora Kinase B / Q000037:antagonists & inhibitors / Q000235:genetics / Q000378:metabolism*; D002460:Cell Line; D045744:Cell Line, Tumor; D020090:Chromosome Segregation / Q000235:genetics / Q000502:physiology*; D004330:Drosophila; D025461:Feedback, Physiological; D006801:Humans; D009685:Nuclear Envelope / Q000235:genetics / Q000378:metabolism*; D054645:Protein Phosphatase 1 / Q000378:metabolism; D054648:Protein Phosphatase 2 / Q000378:metabolism
chemical_list: C576921:AURKB protein, human; D064107:Aurora Kinase B; D054645:Protein Phosphatase 1; D054648:Protein Phosphatase 2