Binds to the promoters of genes with functions important for the G1/S (start) transition; primarily genes involved in DNA synthesis and repair, chromosome segregation, nuclear division and transcription. Regulated in a cell cycle-dependent manner, peaking in G1 phase. Negatively regulated by transcription factor SBF (SWI4-SWI6 cell-cycle box binding factor). Phosphorylated by CDC28. Belongs to the PLM2/TOS4 family.