Subcellular distribution of [125I]iodoaryl beta-methyl fatty acids.

Subcellular distribution studies of two aryl branched-chain and one aryl straight-chain iodinated fatty acids were carried out as part of a continuing effort to determine if such acids are metabolized by beta-oxidation. For the omega-iodoaryl fatty acids, a change in subcellular radioactivity location was observed which was chain-length dependent. Chain lengths of 15 carbons, straight and branched, were largely found in the nuclear-membrane fraction, whereas a chain length of 8 carbons was largely located in the cytosol. No unequivocal evidence for metabolic trapping in the mitochondria was observed for omega-iodoaryl branched-chain fatty acids using the centrifugation technique employed in this study.