For example, histone acetyltransferase (HAT) complexes are thought to activate gene expression by modifying chromatin-associated proteins called histones which function like spools for DNA to wind around.

• 例如,组蛋白乙酰转移酶(HAT)复合物被认为是通过修饰与染色质相连的被称作组蛋白的蛋白质来激活基因表达的过程,而组蛋白的功能是被当作让DNA缠绕的线轴。