Two dynamin-like proteins stabilize FtsZ rings during Streptomyces sporulation

Research output: Contribution to journalArticle

Abstract

During sporulation, the filamentous bacteria Streptomyces undergo a massive cell division event in which the synthesis of ladders of sporulation septa convert multigenomic hyphae into chains of unigenomic spores. This process requires cytokinetic Z-rings formed by the bacterial tubulin homolog FtsZ, and the stabilization of the newly formed Z-rings is crucial for completion of septum synthesis. Here we show that two dynamin-like proteins, DynA and DynB, play critical roles in this process. Dynamins are a family of large, multidomain GTPases involved in key cellular processes in eukaryotes, including vesicle trafficking and organelle division. Many bacterial genomes encode dynamin-like proteins, but the biological function of these proteins has remained largely enigmatic. Using a cell biological approach, we show that the two Streptomyces dynamins specifically localize to sporulation septa in an FtsZ-dependent manner. Moreover, dynamin mutants have a cell division defect due to the decreased stability of sporulation-specific Z-rings, as demonstrated by kymographs derived from time-lapse images of FtsZ ladder formation. This defect causes the premature disassembly of individual Z-rings, leading to the frequent abortion of septum synthesis, which in turn results in the production of long spore-like compartments with multiple chromosomes. Two-hybrid analysis revealed that the dynamins are part of the cell division machinery and that they mediate their effects on Z-ring stability during developmentally controlled cell division via a network of protein–protein interactions involving DynA, DynB, FtsZ, SepF, SepF2, and the FtsZ-positioning protein SsgB.

Details

Authors
Organisations
External organisations
  • John Innes Centre
Research areas and keywords

Subject classification (UKÄ) – MANDATORY

  • Microbiology
  • Cell Biology

Keywords

  • Bacterial dynamins, Cell division, FtsZ, Sporulation, Streptomyces
Original languageEnglish
Pages (from-to)E6176-E6183
JournalProceedings of the National Academy of Sciences of the United States of America
Volume114
Issue number30
Publication statusPublished - 2017 Jul 25
Publication categoryResearch
Peer-reviewedYes