PET imaging of FATPs

Fatty acid transport proteins (FATPs), also known as solute carrier protein family 27 (SLC27) include six proteins which facilitate the transport of long-chain fatty acids (LCFAs) across plasma and intracellular membranes. Vascular endothelial growth factor B (VEGF-B) regulates the expression of FATPs in the endothelial cells. Other LCFA transporters include FABPpm, fatty acid translocase/CD36, and possibly caveolins.

The six FATPs are found in different tissues:

At least FATP1 can translocate from the cytoplasm to the plasma membrane in response to insulin. FATP1 is also found in mitochondria.

FATP2 can function also as acyl-CoA synthetase (ACS), activating long and very long chain FAs.

Fatty acid translocase/CD36

Fatty acid translocase/CD36 (FAT/CD36) is found in the heart and skeletal muscle, intestine, adipose tissue, spleen, platelets, monocytes and macrophages, endothelium, epidermis, kidneys, brain, and liver. It has an important role in regulation of FA oxidation and esterification, but it also has numerous other functions. In leukocytes it even works as a selective sensor of microbial diacylglycerides.

Insulin and muscle contractions can increase cellular LCFA uptake by inducing the translocation of FAT/CD36 to the plasma membrane.

The effect of FAT/CD36 deficiency on FA uptake in humans has been studied with [11C]palmitate PET (Hames et al., 2014).


Caveolae are specialized flask-shaped microdomains of the plasma membrane, which get their shape from caveolin proteins. They contain signalling and receptor proteins, and fatty acid translocase/CD36. Caveolin-1 and caveolin-2 are found in almost all tissues except in the heart and skeletal muscle, which contain caveolin-3. The role of caveolins in FA transport is yet controversial.

See also:


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Updated at: 2017-10-07
Created at: 2015-10-13
Written by: Vesa Oikonen