Particular chromatin modifications are associated with different states of gene transcription, yet our understanding of which modifications are causal ‘drivers’ in promoting transcription is incomplete. Here, we discuss new developments describing the ordered, mechanistic role of select histone marks occurring during distinct steps in the RNA polymerase II (Pol II) transcription cycle. In particular, we highlight the interplay between histone marks in specifying the ‘next step’ of transcription. While many studies have described correlative relationships between histone marks and their occupancy at distinct gene regions, we focus on studies that elucidate clear functional consequences of specific histone marks during different stages of transcription. These recent discoveries have refined our current mechanistic understanding of how histone marks promote Pol II transcriptional progression.

特定的染色质修饰与基因转录的不同状态相关，但我们对哪些修饰是促进转录的因果“驱动器”的理解尚不完全。在这里，我们讨论了新的发展，描述了选择的组蛋白标记在RNA聚合酶II（Pol II）转录周期的不同步骤中发生的有序的机械作用。特别是，我们在指定转录的“下一步”时强调了组蛋白标记之间的相互作用。尽管许多研究描述了组蛋白标记与其在不同基因区域的占有率之间的相关关系，但我们专注于阐明特定组蛋白标记在转录不同阶段的明确功能后果的研究。