Homodimeric ABCD1 associated with the peroxisomal membrane mediates the uptake of cytosolic very long chain fatty acyl CoAs such as hexacosanoyl-CoA into the peroxisomal matrix. While the requirement for this uptake step in the catabolism of very long chain fatty acids is well-established, direct evidence for the function of ABCD1 as a transporter comes only from studies of its ability to restore peroxisomal long chain fatty acid catabolism in yeast strains whose endogenous transporters have been disrupted by mutation. ABCD1 is inferred to function as a dimer like other members of the ABCD transporter family. The energy requirements of peroxisomal fatty acid uptake (other ABCD transporter-mediated reactions are coupled to ATP hydrolysis) have not been established (van Roermund et al. 2008).
van Roermund, CW,
van Cruchten, A,
long-chain fatty acid transporter activity of ABCD1 homodimer [peroxisomal membrane]