DNA ligase 3

LIG3
Available structures
PDB	Ortholog search: PDBe RCSB
List of PDB id codes
	1IMO, 1IN1, 1UW0, 3L2P, 3PC7, 3PC8, 3QVG
Identifiers
Aliases	LIG3, LIG2, DNA ligase 3, LIG3alpha, MTDPS20
External IDs	OMIM: 600940; MGI: 109152; HomoloGene: 32109; GeneCards: LIG3; OMA:LIG3 - orthologs
Gene location (Human)
Chr.	Chromosome 17 (human)
End	35,009,743 bp
Gene location (Mouse)
Chr.	Chromosome 11 (mouse)
End	82,695,100 bp
RNA expression pattern
	Top expressed in
	buccal mucosa cell; ; internal globus pallidus; ; epithelium of colon; ; ganglionic eminence; ; sural nerve; ; body of uterus; ; right testis; ; left testis; ; ventricular zone; ; right uterine tube;
	Top expressed in
	gastrula; ; spermatocyte; ; spermatid; ; seminiferous tubule; ; genital tubercle; ; secondary oocyte; ; ventricular zone; ; zygote; ; tail of embryo; ; submandibular gland;
	More reference expression data
	n/a
Gene ontology
Molecular function	DNA binding; nucleotide binding; zinc ion binding; metal ion binding; ligase activity; protein binding; DNA ligase activity; ATP binding; DNA ligase (ATP) activity;
Cellular component	DNA ligase III-XRCC1 complex; nucleoplasm; nucleus; mitochondrion; cytoplasm;
Biological process	nucleotide-excision repair, DNA gap filling; DNA recombination; lagging strand elongation; DNA biosynthetic process; mitochondrial DNA repair; mitochondrion organization; double-strand break repair via alternative nonhomologous end joining; negative regulation of mitochondrial DNA replication; cellular response to DNA damage stimulus; cell division; DNA ligation; DNA replication; double-strand break repair via homologous recombination; V(D)J recombination; DNA ligation involved in DNA repair; cell cycle; transcription-coupled nucleotide-excision repair; double-strand break repair; DNA repair; base-excision repair, DNA ligation;
	Sources:Amigo / QuickGO
Orthologs
	3980
	16882
	ENSG00000005156
	ENSMUSG00000020697
	P49916
	P97386
	NM_002311; NM_013975
	NM_001291245; NM_001291246; NM_001291247; NM_010716
	NP_002302; NP_039269
	n/a
	Wikidata
View/Edit Human	View/Edit Mouse

DNA ligase 3 also DNA ligase III, is an enzyme that, in humans, is encoded by the LIG3 gene. LIG3 encodes ATP-dependent DNA ligases that seal interruptions in the phosphodiester backbone of duplex DNA.

There are three families of ATP-dependent DNA ligases in eukaryotes. These enzymes utilize the same three step reaction mechanism; (i) formation of a covalent enzyme-adenylate intermediate; (ii) transfer of the adenylate group to the 5' phosphate terminus of a DNA nick; (iii) phosphodiester bond formation. Unlike LIG1 and LIG4 family members that are found in almost all eukaryotes, LIG3 family members are less widely distributed. LIG3 encodes several distinct DNA ligase species by alternative translation initiation and alternative splicing mechanisms that are described below.