PWWP2A variant NuRD complex represses intragenic spurious transcription initiation

H3 trimethylation at K36 deposited over the body of actively transcribed gene, is recognized by readers to modulate the epigenetic states, such as DNA methylation and histone deacetylation, to ensure the proper gene transcription. PWWP2A was identified as the reading component of variant NuRD complex to deacetylate gene bodies in mammalian cells. However, whether this deacetylation affects intragenic transcription is not investigated. Here, we performed CAGE-seq to profile transcription initiation in PWWP2A/B double knockout and fount that intragenic spurious transcription initiations at pre-existing low-level initiation from highly expressed genes were enhanced, accompanying with elevated acetylation level at H3K9 and H3K27, as well as nascent transcription. Additionally, the intragenic spurious transcriptions in PWWP2A/B loss are distinct with those in DNMT3B loss which is prone to produce de novo initiation and lack of PWWP2A/B-related chromatin changes. Collectively, PWWP2A/B-NuRD complex deacetylates active gene bodies to suppress intragenic spurious transcription in mammals. CAGE-seq in E14 and PWWP2A/B double knockouts