LIG1
Description
The LIG1 (DNA ligase 1) is a protein-coding gene located on chromosome 19.
LIG1, also known as DNA ligase I, is an enzyme encoded by the LIG1 gene in humans. It is the only known eukaryotic DNA ligase involved in both DNA replication and repair, making it the most studied ligase. It was discovered in 1967 through the work of Lehman, Gellert, Richardson, and Hurwitz laboratories. LIG1 is a 120 kDa enzyme with 919 residues. It contains three functional domains: an N-terminal DNA binding domain (DBD), a catalytic nucleotidyltransferase (NTase) domain, and a C-terminal oligonucleotide/oligosaccharide binding (OB) domain. The N-terminus of LIG1 contains a replication factory-targeting sequence (RFTS) and a nuclear localization sequence (NLS). The RFTS is used to recruit LIG1 to sites of DNA replication. Activation and recruitment of LIG1 are associated with posttranslational modifications, particularly phosphorylation of four serine residues on the N-terminal domain: Ser51, Ser76, Ser91 by cyclin-dependent kinase (CDK) and Ser66 by casein kinase II (CKII).
LIG1 is also known as IMD96, LIGI, hLig1.
