LigD polymerase domain, type 3 (IPR033652)

Short name: LigD_Pol-like_3

Overlapping homologous superfamilies


Domain relationships


This entry represents a subgroup of polymerase (Pol) domains of bacterial LigD proteins. The LigD Pol domain belongs to the archaeal/eukaryal primase (AEP) superfamily. In prokaryotes, LigD along with Ku is required for non-homologous end joining (NHEJ)-mediated repair of DNA double-strand breaks (DSB) [PMID: 16446439, PMID: 17174332]. NHEJ-mediated DNA DSB repair is error-prone [PMID: 16816388]. It has been suggested that LigD Pol contributes to NHEJ-mediated repair DSB repair in vivo, by filling in short 5'-overhangs with ribonucleotides; the filled in termini would then be sealed by the associated LigD ligase domain, resulting in short stretches of RNA incorporated into the genomic DNA [PMID: 15778718]. The Pol domains of Pseudomonas aeruginosa (PaeLigD; IPR033651) and Mycobacterium tuberculosis (MtLigD; IPR033649) are stimulated by manganese, are error-prone, and prefer adding rNTPs to dNTPs in vitro. However, this subgroup of domains is distinct from PaeLigD and MtLigD, and awaits functional characterization.

Contributing signatures

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