Involved in cell division. Probably acts as a membrane anchor for FstZ2, tethering its filaments to the division site. May be involved in septum closure. Homodimer. Does not oligomerize. Interacts with FtsZ2. Localizes in a ring-like structure at the cell division plane at midcell. Localizes at the future site of cell division straight after the closure of the septum. Co-localizes with FtsZ1 and FtsZ2. FtsZ1 is important for its proper localization. Depletion of this protein leads to formation of large cells with a cragged cell surface, which are unable to establish a cell division plane.