biostudies-literatureRoberts DMSwiss National Science FoundationWellcome Truste2204042119https://www.ebi.ac.uk/biostudies/studies/S-EPMC9564211biostudies-literatureUnknown119(41)SMC complexes, loaded at ParB-<i>parS</i> sites, are key mediators of chromosome organization in bacteria. ParA/Soj proteins interact with ParB/Spo0J in a pathway involving adenosine triphosphate (ATP)-dependent dimerization and DNA binding, facilitating chromosome segregation in bacteria. In <i>Bacillus subtilis</i>, ParA/Soj also regulates DNA replication initiation and along with ParB/Spo0J is involved in cell cycle changes during endospore formation. The first morphological stage in sporulation is the formation of an elongated chromosome structure called an axial filament. Here, we show that a major redistribution of SMC complexes drives axial filament formation in a process regulated by ParA/Soj. Furthermore, and unexpectedly, this regulation is dependent on monomeric forms of ParA/SoProceedings of the National Academy of Sciences of the United States of AmericaChromosome remodelling by SMC/Condensin in <i>B. subtilis</i> is regulated by monomeric Soj/ParA during growth and sporulation.PMC9564211204985/Z/16/Z197770209500Roberts DMAnchimiuk AErrington JMurray HGruber SKloosterman TGWu LJfalseChromosome remodelling by SMC/Condensin in <i>B. subtilis</i> is regulated by monomeric Soj/ParA during growth and sporulation.SMC complexes, loaded at ParB-<i>parS</i> sites, are key mediators of chromosome organization in bacteria. ParA/Soj proteins interact with ParB/Spo0J in a pathway involving adenosine triphosphate (ATP)-dependent dimerization and DNA binding, facilitating chromosome segregation in bacteria. In <i>Bacillus subtilis</i>, ParA/Soj also regulates DNA replication initiation and along with ParB/Spo0J is involved in cell cycle changes during endospore formation. The first morphological stage in sporulation is the formation of an elongated chromosome structure called an axial filament. Here, we show that a major redistribution of SMC complexes drives axial filament formation in a process regulated by ParA/Soj. Furthermore, and unexpectedly, this regulation is dependent on monomeric forms of ParA/So2022-01-01T00:00:00Z2022 Oct2025-04-04T23:03:19.735Z2025-04-04T23:03:19.735ZS-EPMC95642113620637010.1073/pnas.2204042119