Anti-La ribonucleoprotein 1, translational regulator antibodies are used for the immunodetection of the protein encoded by the LARP1 gene. In humans, the canonical protein has a reported length of 1096 amino acid residues and a mass of 123.5 kDa. Its subcellular localization is in the cytoplasm. Alternative splicing is reported to yield 2 different isoforms for this protein. A member of the LARP protein family, it is reported to be a RNA-binding protein that regulates the translation of specific target mRNA species downstream of the mTORC1 complex, in function of growth signals and nutrient availability. Post-translational modifications have been described, including phosphorylation. Other names for this target antigen include Lar1, Lhp1, la-related protein 1, La ribonucleoprotein domain family member 1, and LARP. Gene orthologs have been identified in the mouse, rat, bovine, frog, zebrafish, chimpanzee and chicken species.