Anti-TGS1 antibodies are used in the immunodetection of the protein trimethylguanosine synthase 1. In humans, the canonical protein has a reported length of 853 amino acid residues and a mass of 96.6 kDa. Its subcellular localization is in the nucleus and cytoplasm. It is ubiquitously expressed across many tissue types. A member of a the Trimethylguanosine synthase protein family, TGS1 is known to catalyze the 2 serial methylation steps for the conversion of the 7-monomethylguanosine (m(7)G) caps of snRNAs and snoRNAs to a 2,2,7-trimethylguanosine (m(2,2,7)G) cap structure. Synonyms for this target antigen include CLL-associated antigen KW-2, PRIP-interacting protein with methyltransferase motif, cap-specific guanine-N2 methyltransferase, and trimethylguanosine synthase.