Part of the ABC transporter FtsEX involved in sporulation. May act as an importer, possibly at the top of a hierarchical cascade leading to the correct temporal initiation of sporulation. Acts upstream of the histidine kinases KinA, KinB and KinC, the RapA phosphatase and the Spo0A sporulation protein. Interacts with FtsX. Unlike the E.coli ortholog, localization is not restricted to division septa, nor is localization dependent on FtsZ. Cells lacking this gene and ftsX, the next gene in the operon, delay sporulation onset, as a result of which they form a medial rather than polar septum at the onset of sporulation. This is presumably due to slower phosphorylation and activation of the spo0A transcriptional regulator. However, at later time points these cells undergo polar division and eventually form smaller than wild-type mature spores. Belongs to the ABC transporter superfamily.