SLC25A17 (solute carrier family 25 member 17), also known as PMP34, is a peroxisomal membrane transporter that mediates cofactor import essential for peroxisomal metabolism. The protein functions as a counter-exchanger, transporting free coenzyme A (CoA), flavin adenine dinucleotide (FAD), and nicotinamide adenine dinucleotide (NAD+) from the cytosol into the peroxisomal matrix in exchange for intraperoxisomally generated adenosine 3',5'-diphosphate (PAP), flavin mononucleotide (FMN), and adenosine monophosphate (AMP) 1. The transporter also facilitates transport of adenosine diphosphate (ADP) and other cofactors at lower efficiency 1. SLC25A17 maintains peroxisomal redox homeostasis by regulating glutathione and NAD(P)H metabolism across the peroxisomal membrane 2. While knockout mice lacking functional SLC25A17 show minimal phenotype under standard conditions, they display hepatomegaly and impaired phytanic and pristanic acid degradation upon dietary phytol challenge, indicating specialized roles in branched fatty acid metabolism 3. Clinically, elevated SLC25A17 expression correlates with poor prognosis in head and neck squamous cell carcinoma and prostate cancer, where it promotes drug resistance through metabolic reprogramming 45. Additionally, SLC25A17 genetic variants associate with Alzheimer's disease risk through effects on hippocampal mitochondrial function 6.