show Abstracthide AbstractPrecise control of the cell cycle is central to the physiology of all cells. In prior work we demonstrated that archaeal cells maintain a constant cell size; however, the regulatory mechanisms underlying the cell cycle remain unexplored in this domain of life. In this study we use genetics, functional genomics, and quantitative imaging to identify and characterize the CdrSL gene regulatory network in a model species of archaea. We demonstrate the central role of these ribbon-helix-helix family transcription factors in the regulation of cell division. In this GEO series related to this study, we use ChIP-seq analysis to demonstrate the binding of CdrL to the upstream region of the cdrS-ftsZ2 locus. We conclude that the CdrSL-Z2 transcriptional network is required to coordinate cell division with cell growth in archaea. Overall design: Examination of CdrL binding sites in the halophilic archaeon Halobacterium salinarum in mid-logarithmic and stationary phases of growth.