Anti-LIP antibodies enable researchers to detect and measure the LIP antigen in biological samples. This target is a reported synonym of the SMG1 gene, which encodes SMG1 nonsense mediated mRNA decay associated PI3K related kinase. This protein is known to function in DNA damage pathways and DNA repair, among other biological roles. The human version of LIP has a canonical amino acid length of 3661 residues and a protein mass of 410.5 kilodaltons, although 4 isoforms have been identified. It is reported to be localized in the nucleus and cytoplasm of cells and widely expressed in many tissue types. Other names for this target antigen include 61E3.4 and ATX.