biostudies-literatureViolante SNIDDK NIH HHSNational Institute of Diabetes and Digestive and Kidney DiseasesNational Institutes of Health4355-4364https://www.ebi.ac.uk/biostudies/studies/S-EPMC6404569biostudies-literatureUnknown33(3)Peroxisomes are essential organelles for the specialized oxidation of a wide variety of fatty acids, but they are also able to degrade fatty acids that are typically handled by mitochondria. Using a combination of pharmacological inhibition and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein 9 genome editing technology to simultaneously manipulate peroxisomal and mitochondrial fatty acid β-oxidation (FAO) in HEK-293 cells, we identified essential players in the metabolic crosstalk between these organelles. Depletion of carnitine palmitoyltransferase (CPT)2 activity through pharmacological inhibition or knockout (KO) uncovered a significant residual peroxisomal oxidation of lauric and palmitic acid, leading to the production of peroxisomal acylcaFASEB journal : official publication of the Federation of American Societies for Experimental BiologyPeroxisomes can oxidize medium- and long-chain fatty acids through a pathway involving ABCD3 and HSD17B4.PMC6404569R01DK113172R01 DK113172Hagen JWaterham HRArgmann CAAchetib NYu CHouten SMVaz FMViolante Svan Roermund CWTChen HBaes MDodatko TfalsePeroxisomes can oxidize medium- and long-chain fatty acids through a pathway involving ABCD3 and HSD17B4.Peroxisomes are essential organelles for the specialized oxidation of a wide variety of fatty acids, but they are also able to degrade fatty acids that are typically handled by mitochondria. Using a combination of pharmacological inhibition and clustered regularly interspaced short palindromic repeats (CRISPR)-CRISPR associated protein 9 genome editing technology to simultaneously manipulate peroxisomal and mitochondrial fatty acid β-oxidation (FAO) in HEK-293 cells, we identified essential players in the metabolic crosstalk between these organelles. Depletion of carnitine palmitoyltransferase (CPT)2 activity through pharmacological inhibition or knockout (KO) uncovered a significant residual peroxisomal oxidation of lauric and palmitic acid, leading to the production of peroxisomal acylca2019-01-01T00:00:00Z2019 Mar2026-06-04T11:18:16.851Z2025-06-01T04:03:38.348ZS-EPMC64045693054049410.1096/fj.201801498R10.1096/fj.201801498r