FABP5 (also known as epidermal FABP, E-FABP, cutaneous fatty-acid-binding protein, C-FABP, psoriasis-associated fatty-acid-binding protein, KFABP, PA-FABP) binds a wide array of ligands. It is an intracellular carrier for long-chain fatty acids and related active lipids, and also selectively delivers specific fatty acids from the cytosol to the nucleus. Its ligands include vitamin A metabolite all-trans-retinoic acid, endocannabinoid and numerous synthetic drugs and probes. It may be involved in keratinocyte differentiation. Mouse FABP5 is found only in the monomeric form; however, human FABP5 can exist as a monomer as well as a domain-swapped dimer. This subgroup belongs to the intracellular fatty-acid binding protein (FABP) family, members of which are small proteins that 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.",