Protein/DNA interactions involving ATF/AP1‐, CCAAT‐, and HiNF‐D‐related factors in the human H3‐ST519 histone promoter: Cross‐competition with transcription regulatory sites in cell cycle controlled H4 and H1 histone genes

Protein/DNA interactions of the H3‐ST519 histone gene promoter were analyzed in vitro. Using several assays for sequence specificity, we established binding sites for ATF/AP1‐, CCAAT‐, and HiNF‐D related DNA binding proteins. These binding sites correlate with two genomic protein/DNA interaction domains previously established for this gene. We show that each of these protein/DNA interactions has a counterpart in other histone genes: H3‐ST519 and H4‐F0108 histone genes interact with ATF‐ and HiNF‐D related binding activities, whereas H3‐ST519 and H1‐FNC16 histone genes interact with the same CCAAT‐box binding activity. These factors may function in regulatory coupling of the expression of different histone gene classes. We discuss these results within the context of established and putative protein/DNA interaction sites in mammalian histone genes. This model suggests that heterogeneous permutations of protein/DNA interaction elements, which involve both general and cell cycle regulated DNA binding proteins, may govern the cellular competency to express and coordinately control multiple distinct histone genes.