MinCD-dependent regulation of the polarity of SpoIIIE assembly and DNA transfer.
During Bacillus subtilis sporulation, the SpoIIIE DNA translocase moves a trapped chromosome across the sporulation septum into the forespore. The direction of DNA translocation is controlled by the specific assembly of SpoIIIE in the mother cell and subsequent export of DNA into the forespore. We present evidence that the MinCD heterodimer, which spatially regulates cell division during vegetative growth, serves as a forespore-specific inhibitor of SpoIIIE assembly. The deletion of minCD increases the ability of forespore-expressed SpoIIIE to assemble and translocate DNA, and causes otherwise wild-type cells to reverse the direction of DNA transfer, producing anucleate forespores. We propose that two distinct mechanisms ensure the specific assembly of SpoIIIE in the mother cell, the partitioning of more SpoIIIE molecules into the larger mother cell by asymmetric cell division and the MinCD-dependent repression of SpoIIIE assembly in the forespore. Our results suggest that the ability of MinCD to sense positional information is utilized during sporulation to regulate protein assembly differentially on the two faces of the sporulation septum.
Sharp
Marc D
MD
Division of Biological Sciences, University of California, San Diego, 9500 Gilman Drive, La Jolla, CA 92093-0349, USA.
Pogliano
Kit
K
D000251:Adenosine Triphosphatases / Q000172:deficiency / Q000235:genetics / Q000502:physiology*; D001412:Bacillus subtilis / Q000235:genetics / Q000502:physiology* / Q000648:ultrastructure; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism* / Q000502:physiology*; D002455:Cell Division; D016764:Cell Polarity / Q000502:physiology; D002876:Chromosomes, Bacterial; D029968:Escherichia coli Proteins; D046911:Macromolecular Substances; D011993:Recombinant Fusion Proteins / Q000378:metabolism; D017384:Sequence Deletion; D012808:Sigma Factor; D013171:Spores, Bacterial; D014157:Transcription Factors
D001426:Bacterial Proteins; D029968:Escherichia coli Proteins; D046911:Macromolecular Substances; C080466:MinC protein, Bacteria; D011993:Recombinant Fusion Proteins; D012808:Sigma Factor; D014157:Transcription Factors; C092468:spoIIR protein, Bacillus subtilis; C030069:spore-specific proteins, Bacillus; D000251:Adenosine Triphosphatases; C072069:MinD protein, E coli