Sequence-directed DNA export guides chromosome translocation during sporulation in Bacillus subtilis.
In prokaryotes, the transfer of DNA between cellular compartments is essential for the segregation and exchange of genetic material. SpoIIIE and FtsK are AAA+ ATPases responsible for intercompartmental chromosome translocation in bacteria. Despite functional and sequence similarities, these motors were proposed to use drastically different mechanisms: SpoIIIE was suggested to be a unidirectional DNA transporter that exports DNA from the compartment in which it assembles, whereas FtsK was shown to establish translocation directionality by interacting with highly skewed chromosomal sequences. Here we use a combination of single-molecule, bioinformatics and in vivo fluorescence methodologies to study the properties of DNA translocation by SpoIIIE in vitro and in vivo. These data allow us to propose a sequence-directed DNA exporter model that reconciles previously proposed models for SpoIIIE and FtsK, constituting a unified model for directional DNA transport by the SpoIIIE/FtsK family of AAA+ ring ATPases.
Ptacin
Jerod L
JL
Department of Molecular and Cell Biology, 642 Stanley Hall, University of California, Berkeley, California 94720, USA.
Nollmann
Marcelo
M
Becker
Eric C
EC
Cozzarelli
Nicholas R
NR
Pogliano
Kit
K
Bustamante
Carlos
C
D000251:Adenosine Triphosphatases / Q000378:metabolism; D001412:Bacillus subtilis / Q000166:cytology / Q000378:metabolism / Q000502:physiology*; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D001692:Biological Transport; D002876:Chromosomes, Bacterial / Q000378:metabolism*; D004269:DNA, Bacterial / Q000378:metabolism; D049452:Green Fluorescent Proteins / Q000235:genetics / Q000378:metabolism; D008565:Membrane Proteins / Q000378:metabolism; D013171:Spores, Bacterial / Q000378:metabolism
D001426:Bacterial Proteins; D004269:DNA, Bacterial; D008565:Membrane Proteins; C030069:spore-specific proteins, Bacillus; D049452:Green Fluorescent Proteins; D000251:Adenosine Triphosphatases