Identification of sequences in a yeast histone promoter involved in periodic transcription.

Sequences between a pair of divergently transcribed histone genes in Saccharomyces cerevisiae are able to confer periodic transcription during the cell cycle. This conclusion contrasts to our previous hypothesis that an ars (autonomously replicating sequence) 3' to this locus is a transcription timer for yeast histone genes. The promoter sequences required for periodic expression have been localized by deletion analysis, and isolated elements have been analyzed by insertion into a heterologous promoter. Two cell-cycle-specific promoter functions have been identified. One function activates transcription in a cell-cycle-dependent manner. The other periodically represses transcription. Negative regulation may be the predominant form of cell-cycle control, because removal of the repressing function results in constitutive expression of the histone genes.