Three copies of the histone gene repeat unit (each repeat contains one copy of each of His1, His2A, His2B, His3 and His4). Each copy of the His3 gene has been mutated to contain the amino acid replacement K18R and each copy of the His4 gene has been mutated to contain the amino acid replacement K8R.
Wild-type His1 gene in the context of a histone gene repeat unit.
Wild-type His2A gene in the context of a histone gene repeat unit.
Wild-type His2B gene in the context of a histone gene repeat unit.
Mutated His3 gene in the context of a histone gene repeat unit; contains a K18R amino acid replacement (mutation to a non-acetylatable residue).
Mutated His4 gene in the context of a histone gene repeat unit; contains a K8R amino acid replacement (mutation to a non-acetylatable residue).