FABP5

FABP5 Full Name

fatty acid binding protein 5 (psoriasis-associated)

FABP5 Introduction

FABP5 (fatty acid binding protein 5), is a lipid-binding intracellular carrier that belongs to the fatty acid binding protein family. FABP5 shuttles long-chain fatty acids and other hydrophobic ligands to multiple intracellular organelles. It is highly expressed in epidermal cells, adipocytes, macrophages and some cancer cells. FABP5 contains a β-barrel structure that creates a hydrophobic pocket with affinity to various ligands that can reversibly bind to FABP5. This allows it to serve as an intracellular lipid sensor. FABP5 is one of the important proteins in mediating the cross-talk between lipid uptake and transport, and intracellular metabolic signalling. It is also one of the proteins which is inducible by dietary lipids, inflammatory stimuli and metabolic stress.

Figure 1. The role and mechanism of FABP5 in lipid metabolism, homeostasis, cell proliferation and differentiation.(Source: Xu B, et al.; 2022)

Functionally, FABP5 regulates lipid metabolism. This includes shuttling fatty acids to the site of oxidation for energy production, to membranes for biosynthesis of cellular components, and to nuclear receptors for activation of transcription. FABP5 is best known for its role as a transporter to peroxisome proliferator–activated receptor β/δ (PPARβ/δ), by which it controls transcriptional programs that modulate energy utilization, inflammation and cell proliferation. FABP5 is also involved in epidermal barrier formation, immune regulation, and glucose–lipid homeostasis. FABP5 binds oxidized lipids, and can modulate inflammatory signaling and thus plays a role in metabolic–immune crosstalk.

Abnormal FABP5 expression is associated with several diseases. In some cancers, FABP5 is overexpressed and oncogenic. FABP5 drives cell proliferation, migration and therapy resistance in part through activation of lipid-mediated signaling pathways. FABP5 has been associated with insulin resistance, obesity-associated inflammation and nonalcoholic fatty liver disease in the context of metabolic diseases, through dysregulation of fatty acid metabolism. Abnormal FABP5 activity has been linked to psoriasis and skin barrier impairment in skin. In addition, neuroinflammation and microglial activation link FABP5 to neurodegenerative disease. In the context of its myriad pathologic connections, FABP5 is being investigated as a biomarker and drug target in cancer, metabolic disease and inflammation.

Alternate Names for FABP5

FABP5; fatty acid binding protein 5 (psoriasis-associated); EFABP; KFABP; E-FABP; PAFABP; PA-FABP; fatty acid-binding protein, epidermal; epidermal-type fatty acid-binding protein; psoriasis-associated fatty acid-binding protein homolog;

• 1. Xu B, et al.; The Biological Functions and Regulatory Mechanisms of Fatty Acid Binding Protein 5 in Various Diseases. Front Cell Dev Biol. 2022, 10:857919.