Forms part of a two-component regulatory system CtrA/CckA that controls multiple events in the cell cycle, including cell division, stalk synthesis and cell cycle-specific transcription. Binds to a group of cell cycle-regulated promoters critical for DNA replication, DNA methylation, and class II flagellar biogenesis. Phosphorylated by CckA. Degraded by the ClpXP protease (PubMed:9755166).