Anti-NCS1 antibodies are used in the immunodetection of the protein neuronal calcium sensor 1. In humans, the canonical protein has a reported length of 190 amino acid residues and a mass of 21.9 kDa. Its subcellular localization is in the cell membrane, golgi, and cytoplasm. Alternative splicing is reported to yield 2 different isoforms for this protein. The NCS1 protein is a member of the Recoverin protein family. Synonyms for this target antigen include FREQ, frequenin homolog, frequenin-like protein, frequenin-like ubiquitous protein, and FLUP.