title: ParA and ParB coordinate chromosome segregation with cell elongation and division during Streptomyces sporulation.
abstract: In unicellular bacteria, the ParA and ParB proteins segregate chromosomes and coordinate this process with cell division and chromosome replication. During sporulation of mycelial Streptomyces, ParA and ParB uniformly distribute multiple chromosomes along the filamentous sporogenic hyphal compartment, which then differentiates into a chain of unigenomic spores. However, chromosome segregation must be coordinated with cell elongation and multiple divisions. Here, we addressed the question of whether ParA and ParB are involved in the synchronization of cell-cycle processes during sporulation in Streptomyces To answer this question, we used time-lapse microscopy, which allows the monitoring of growth and division of single sporogenic hyphae. We showed that sporogenic hyphae stop extending at the time of ParA accumulation and Z-ring formation. We demonstrated that both ParA and ParB affect the rate of hyphal extension. Additionally, we showed that ParA promotes the formation of massive nucleoprotein complexes by ParB. We also showed that FtsZ ring assembly is affected by the ParB protein and/or unsegregated DNA. Our results indicate the existence of a checkpoint between the extension and septation of sporogenic hyphae that involves the ParA and ParB proteins.
authors.affiliation: Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14A, Wrocław 50-383, Poland.
authors.forename: Magdalena
authors.initials: M
authors.lastname: Donczew
authors.affiliation: Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14A, Wrocław 50-383, Poland.
authors.forename: Paweł
authors.initials: P
authors.lastname: Mackiewicz
authors.affiliation: Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14A, Wrocław 50-383, Poland.
authors.forename: Agnieszka
authors.initials: A
authors.lastname: Wróbel
authors.affiliation: Department of Biology, Lund University, Sölvegatan 35, Lund 22362, Sweden.
authors.forename: Klas
authors.initials: K
authors.lastname: Flärdh
authors.affiliation: Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14A, Wrocław 50-383, Poland Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, Wrocław 53-114, Poland.
authors.forename: Jolanta
authors.initials: J
authors.lastname: Zakrzewska-Czerwińska
authors.affiliation: Faculty of Biotechnology, University of Wrocław, Joliot-Curie 14A, Wrocław 50-383, Poland Ludwik Hirszfeld Institute of Immunology and Experimental Therapy, Polish Academy of Sciences, Weigla 12, Wrocław 53-114, Poland dagmara.jakimowicz@uni.wroc.pl.
authors.forename: Dagmara
authors.identifier: http://orcid.org/0000-0002-7857-064X
authors.initials: D
authors.lastname: Jakimowicz
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism*; D002455:Cell Division; D047369:Chromatin Immunoprecipitation; D020090:Chromosome Segregation; D004269:DNA, Bacterial / Q000378:metabolism; D005453:Fluorescence; D025301:Hyphae / Q000254:growth & development / Q000378:metabolism; D008954:Models, Biological; D013171:Spores, Bacterial / Q000166:cytology* / Q000378:metabolism*; D013302:Streptomyces / Q000166:cytology* / Q000235:genetics*; D013997:Time Factors
chemical_list: D001426:Bacterial Proteins; D004269:DNA, Bacterial
keywords: ParAB; Streptomyces; bacterial cell division; bacterial cell growth; chromosome segregation; sporulation