THE SPOIIE LOCUS IS INVOLVED IN THE SPO0A-DEPENDENT SWITCH IN THE LOCATION OF FTSZ RINGS IN BACILLUS-SUBTILIS

A switch in the location of FtsZ ring structures from medial to polar is one of the earliest morphological indicators of sporulation in Baci llus subtilis. This switch can be artificially caused during vegetativ e growth by induction of an active form, Sad67, of the transcription r egulator, Spo0A (P. A. Levin and R. Losick, Genes Dev. 10:478-488, 199 6). We have used immunofluorescence microscopy to show that the switch in FtsZ ring location during vegetative growth caused by Sad67 induct ion is blocked by a spoIIE deletion mutation. The spoIIE mutation also impaired polar FtsZ ring formation during sporulation. These results suggest that SpoIIE mediates the Spo0A-directed formation of polar Fts Z rings.