HEXIM (IPR024872)

Short name: HEXIM

Overlapping homologous superfamilies


Family relationships

  • HEXIM (IPR024872)


Hexamethylene bisacetamide-inducible proteins (HEXIMs) are transcriptional regulators that function as general RNA polymerase II transcription inhibitors. HEXIMs, aided by the 7SK snRNA, sequester positive transcriptional elongation factor b (P-TEFb) into a large inactive 7SK snRNP complex [PMID: 14580347, PMID: 15713661]. This prevents P-TEFb from phosphorylating RNA polymerase II and blocks subsequent transcriptional elongation.

Two HEXIM family members have been identified in mammals, termed HEXIM1 and HEXIM2, which exhibit distinct expression patterns [PMID: 15713661].

GO terms

Biological Process

GO:0000122 negative regulation of transcription by RNA polymerase II

Molecular Function

GO:0004861 cyclin-dependent protein serine/threonine kinase inhibitor activity
GO:0017069 snRNA binding

Cellular Component

GO:0005737 cytoplasm
GO:0005634 nucleus

Contributing signatures

Signatures from InterPro member databases are used to construct an entry.