Involved in cell division. Plays an important role in septal peptidoglycan synthesis and cell shape morphogenesis. May facilitate the recruitment of the peptidoglycan synthesis machinery to poles and septal zones and coordinate peptidoglycan synthesis at these sites. Interacts with multiple cell division proteins such as FtsZ, PbpB (PBP3, FtsI), FtsQ, PBPA and CwsA. Localizes to midcell sites in an FtsZ-dependent manner and colocalizes with FtsZ. Localizes at septa, at poles and on membranes. Belongs to the CrgA family.