Lipocalin-1 belongs to the lipocalin family. Lipocalins are a group of extracellular proteins that are able to bind lipophiles by enclosure within their structures to minimize solvent contact. This protein may bind hydrophobic ligands and inhibit cysteine proteinases. It may also play a role in taste reception.

Based on the known 3-dimensional structure of 5 members of the lipocalin family, i.e., retinol binding protein , beta-lactoglobulin, bilin binding protein, mouse major urinary protein, and rat urinary alpha-2-globulin, the general architecture appears to be highly appropriate for binding a variety of hydrophobic ligands. On the basis of highly conserved amino acid sequences and of a size around 18 to 20 kD, about 20 proteins have been designated as lipocalins.