lipocalin similar to human epididymal-specific lipocalin-8, mouse lipocalin-5 and -8, and similar proteins
Lipocalin 5 (LCN5; also known as epididymal retinoic acid binding protein Erabp, mouse epididymal protein 10, MEP10, and E-RABP) and Lipocalin 8 (LCN8; also known as mouse epididymal protein 17, MEP17) are homologous proteins belonging to the epididymis-specific lipocalins; they may play a role in male fertility, and may act as retinoid carrier proteins within the epididymis. In mice, genes encoding the two proteins are contiguous; in humans, there is one gene LCN8 (which has been previously called LCN5). This group belongs to the lipocalin/cytosolic fatty-acid binding protein family which have a large beta-barrel ligand-binding cavity. Lipocalins are mainly low molecular weight extracellular proteins that bind principally small hydrophobic ligands, and form covalent or non-covalent complexes with soluble macromolecules, as well as membrane bound-receptors. They participate in processes such as ligand transport, modulation of cell growth and metabolism, regulation of immune response, smell reception, tissue development and animal behavior. Cytosolic fatty-acid binding proteins, also bind hydrophobic ligands in a non-covalent, reversible manner, and have been implicated in intracellular uptake, transport and storage of hydrophobic ligands, regulation of lipid metabolism and sequestration of excess toxic fatty acids, as well as in signaling, gene expression, inflammation, cell growth and proliferation, and cancer development.
Jiyao W et al.(2023). "The conserved domain database in 2023.",