TY - JOUR TI - ParB spreading on DNA requires cytidine triphosphate in vitro AU - Jalal, Adam SB AU - Tran, Ngat T AU - Le, Tung BK A2 - Vecchiarelli, Anthony G A2 - Storz, Gisela A2 - Vecchiarelli, Anthony G VL - 9 PY - 2020 DA - 2020/02/20 SP - e53515 C1 - eLife 2020;9:e53515 DO - 10.7554/eLife.53515 UR - https://doi.org/10.7554/eLife.53515 AB - In all living organisms, it is essential to transmit genetic information faithfully to the next generation. The SMC-ParAB-parS system is widely employed for chromosome segregation in bacteria. A DNA-binding protein ParB nucleates on parS sites and must associate with neighboring DNA, a process known as spreading, to enable efficient chromosome segregation. Despite its importance, how the initial few ParB molecules nucleating at parS sites recruit hundreds of further ParB to spread is not fully understood. Here, we reconstitute a parS-dependent ParB spreading event using purified proteins from Caulobacter crescentus and show that CTP is required for spreading. We further show that ParB spreading requires a closed DNA substrate, and a DNA-binding transcriptional regulator can act as a roadblock to attenuate spreading unidirectionally in vitro. Our biochemical reconstitutions recapitulate many observed in vivo properties of ParB and opens up avenues to investigate the interactions between ParB-parS with ParA and SMC. KW - Caulobacter crescentus KW - ParB-parS KW - CTP KW - chromosome segregation KW - chromosome organization KW - spreading JF - eLife SN - 2050-084X PB - eLife Sciences Publications, Ltd ER -