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bioRxiv · 10.1101/2021.06.14.448280

Peroxisomal ATP uptake is managed by the ABC transporters and two adenine nucleotide transporters

Roermund, C. W. T. v.·IJlst, L.·Linka, N.·Wanders, R. J. A.·Waterham, H. R.
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Abstract

Peroxisomes are essential organelles involved in various metabolic processes, including fatty acid {beta}-oxidation. Their metabolic functions require a controlled exchange of metabolites and co-factors, including ATP across the peroxisomal membrane. We investigated which proteins are involved in the peroxisomal uptake of ATP in the yeast Saccharomyces cerevisiae. Using wild-type and targeted deletion strains, we measured ATP-dependent peroxisomal octanoate {beta}-oxidation, intra-peroxisomal ATP levels employing peroxisome-targeted ATP-sensing reporter proteins, and ATP uptake in proteoliposomes prepared from purified peroxisomes. We show that intra-peroxisomal ATP levels are maintained by different peroxisomal membrane proteins each with different modes of action: (1) the previously reported Ant1p protein, which catalyzes ATP/AMP exchange (2) the ABC transporter protein complex Pxa1p/Pxa2p, which mediates both acyl-CoA and ATP uptake; and; (3) the mitochondrial Aac2p protein, which catalyzes ATP/ADP exchange and was shown to have a dual localization in both mitochondria and peroxisomes. Our results provide compelling evidence for an ingenious complementary system for the uptake of ATP in peroxisomes.

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Roermund, C. W. T. v., IJlst, L., Linka, N., Wanders, R. J. A., Waterham, H. R.. 2021-06-14. Peroxisomal ATP uptake is managed by the ABC transporters and two adenine nucleotide transporters. https://doi.org/10.1101/2021.06.14.448280

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