biostudies-literatureMeschichi AVetenskapsrådetCarl Tryggers Stiftelse för Vetenskaplig ForskningHorizon 2020 Framework ProgrammeKnut och Alice Wallenbergs StiftelseLABoratoires d’EXcellence ARCANEe54736https://www.ebi.ac.uk/biostudies/studies/S-EPMC9724665biostudies-literatureUnknown23(12)Homologous recombination (HR) is a conservative DNA repair pathway in which intact homologous sequences are used as a template for repair. How the homology search happens in the crowded space of the cell nucleus is, however, still poorly understood. Here, we measure chromosome and double-strand break (DSB) site mobility in Arabidopsis thaliana, using lacO/LacI lines and two GFP-tagged HR reporters. We observe an increase in chromatin mobility upon the induction of DNA damage, specifically at the S/G2 phases of the cell cycle. This increase in mobility is lost in the sog1-1 mutant, a central transcription factor of the DNA damage response in plants. Also, DSB sites show particularly high mobility levels and their enhanced mobility requires the HR factor RAD54. Our data suggest that repair mEMBO reportsThe plant-specific DDR factor SOG1 increases chromatin mobility in response to DNA damage.PMC97246652018‐04101ANR‐10‐LABX‐41MSCA‐IF 1010327102019‐006218:3502018‐04214Rosa SMeschichi AZhao LDa Ines OWhite CReeck SSicard APontvianne FfalseThe plant-specific DDR factor SOG1 increases chromatin mobility in response to DNA damage.Homologous recombination (HR) is a conservative DNA repair pathway in which intact homologous sequences are used as a template for repair. How the homology search happens in the crowded space of the cell nucleus is, however, still poorly understood. Here, we measure chromosome and double-strand break (DSB) site mobility in Arabidopsis thaliana, using lacO/LacI lines and two GFP-tagged HR reporters. We observe an increase in chromatin mobility upon the induction of DNA damage, specifically at the S/G2 phases of the cell cycle. This increase in mobility is lost in the sog1-1 mutant, a central transcription factor of the DNA damage response in plants. Also, DSB sites show particularly high mobility levels and their enhanced mobility requires the HR factor RAD54. Our data suggest that repair m2022-01-01T00:00:00Z2022 Dec2025-05-29T22:09:21.846Z2025-05-29T22:09:21.846ZS-EPMC97246653627839510.15252/embr.202254736