HIR/HIRA,one of the histone chaperones,encoded by Hir/Hira(histone regulation) genes,were initially identified in yeast as negative regulators of histone gene expression.

• Hir/Hira基因产物HIR/HIRA为组蛋白的伴侣蛋白,最先作为组蛋白基因表达的一种负调节因子从酵母中被鉴定出来。