RT Journal Article
SR Electronic
T1 The C-terminal domain of ParB is critical for dynamic DNA binding and bridging interactions which condense the bacterial centromere
JF bioRxiv
FD Cold Spring Harbor Laboratory
SP 122986
DO 10.1101/122986
A1 Gemma L. M. Fisher
A1 César L. Pastrana
A1 Victoria A. Higman
A1 Alan Koh
A1 James A. Taylor
A1 Annika Butterer
A1 Timothy D. Craggs
A1 Frank Sobott
A1 Heath Murray
A1 Matthew P. Crump
A1 Fernando Moreno-Herrero
A1 Mark S. Dillingham
YR 2017
UL http://biorxiv.org/content/early/2017/04/01/122986.abstract
AB The ParB protein forms DNA bridging interactions around parS to form networks which condense DNA and earmark the bacterial chromosome for segregation. The mechanism underlying the formation of ParB nucleoprotein complexes is unclear. We show here that the central DNA binding domain is essential for anchoring at parS, and that this interaction is not required for DNA condensation. Structural analysis of the C-terminal domain reveals a dimer with a lysine-rich surface that binds DNA non-specifically and is essential for DNA condensation in vitro. Mutation of either the dimerisation or the DNA binding interface eliminates ParB foci formation in vivo. Moreover, the free C-terminal domain can rapidly decondense ParB networks independently of its ability to bind DNA. Our work reveals a dual role for the C-terminal domain of ParB as both a DNA binding and bridging interface, and highlights the dynamic nature of ParB networks.