Helicase XPB/Ssl2 (IPR001161)

Short name: XPB/Ssl2

Overlapping homologous superfamilies

Family relationships


XPB/Ssl2 helicase (also known as Ercc3/RepB/XPB/Rad25/Ssl2/haywire) is a core subunit of the eukaryotic basal transcription factor complex TFIIH which plays a dual role in transcription and DNA repair [PMID: 25641424]. It is involved in nucleotide excision repair (NER) of DNA and in RNA transcription by RNA polymerase II [PMID: 10024882]. The TFIIH multiprotein complex consists of a 7-subunit core (XPB, p62, p52, p44, p34, and TTDA) that is associated with a 3-subunit CDK-activating kinase module (MAT1, cyclin H and Cdk7) [PMID: 21592869]. It acts by opening DNA either around the RNA transcription start site or the DNA damage [PMID: 14534314].

Defects in XPB are the cause of xeroderma pigmentosum complementation group B (XP-B); also known as xeroderma pigmentosum II (XP2) or XP group B (XPB) or xeroderma pigmentosum group B combined with Cockayne syndrome (XP-B/CS) [PMID: 8304337, PMID: 16947863]. Defects in XPB are also a cause of trichothiodystrophy photosensitive (TTDP) [PMID: 9012405].

GO terms

Biological Process

GO:0006289 nucleotide-excision repair
GO:0006367 transcription initiation from RNA polymerase II promoter

Molecular Function

GO:0004003 ATP-dependent DNA helicase activity

Cellular Component

No terms assigned in this category.

Contributing signatures

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