ATP-Driven Separation of Liquid Phase Condensates in Bacteria Auteur(s): Guilhas Baptiste, Walter J.-C., Rech Jerome, David G., Walliser N.-O., Palmeri J., Mathieu-Demaziere Céline, Parmeggiani A., Bouet Jean-Yves, Le Gall Antoine, Nollmann Marcelo (Article) Publié: Molecular Cell, vol. 79 p.293-303 (2020) Texte intégral en Openaccess : Ref HAL: hal-02391672_v1 Ref Arxiv: 2010.00214 DOI: 10.1016/j.molcel.2020.06.034 WoS: 000575919900012 Ref. & Cit.: NASA ADS Exporter : BibTex | endNote Résumé: Liquid-liquid phase-separated (LLPS) states are key to compartmentalizing components in the absence of membranes; however, it is unclear whether LLPS condensates are actively and specifically organized in the subcellular space and by which mechanisms. Here, we address this question by focusing on the ParABS DNA segregation system, composed of a centromeric-like sequence (parS), a DNA-binding protein (ParB), and a motor (ParA). We show that parS and ParB associate to form nanometer-sized, round condensates. ParB molecules diffuse rapidly within the nucleoid volume but display confined motions when trapped inside ParB condensates. Single ParB molecules are able to rapidly diffuse between different condensates, and nucleation is strongly favored by parS. Notably, the ParA motor is required to prevent the fusion of ParB condensates. These results describe a novel active mechanism that splits, segregates, and localizes non-canonical LLPS condensates in the subcellular space. |