Table 1 Isoform-specific functions of BRD4

Serves as transcriptional co-activator

[41, 42]

BRD4 isoform long (BRD4-L)

Promotes RNA transcription via RNA Polymerase II pause-release

[41,42,43]

Has intrinsic histone acetyltransferase activity

[44]

Maintains higher-order chromatin structure

[38]

Induces expression of genes involved in the DNA repair pathway NHEJ

[15, 16]

Provides structural support for NHEJ protein complex

[15, 16, 45]

Regulates transcription of primary response genes

[17]

Regulates transcription of antioxidant genes via interaction with NRF2

[18]

Indirectly induces generation of ROS via KEAP1-NRF2 pathway

[46]

Has transformative potential in epithelial ovarian cells

[10]

Predominantly binds to lysine-acetylated histones

[38]

BRD4 isoform short (BRD4-S)

Promotes chromatin compaction

[38]

Incorporates BRD4 condensation into the chromatin

[39]

Sustains transcription of proliferative genes in cancer cells via phase separation

[39]

Inhibits DNA damage repair

[15, 47]

Promotes oncogenic properties in cancer

[10, 28, 30]