van Roermund Carlo W T, IJlst Lodewijk, Linka Nicole, Wanders Ronald J A, Waterham Hans R
Laboratory Genetic Metabolic Diseases, Amsterdam Gastroenterology, Endocrinology and Metabolism, Amsterdam University Medical Centers-Location AMC, University of Amsterdam, Amsterdam, Netherlands.
Department of Plant Biochemistry, Heinrich-Heine University Düsseldorf, Düsseldorf, Germany.
Front Cell Dev Biol. 2022 Jan 19;9:788921. doi: 10.3389/fcell.2021.788921. eCollection 2021.
Peroxisomes are essential organelles involved in various metabolic processes, including fatty acid β-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 . Using wild-type and targeted deletion strains, we measured ATP-dependent peroxisomal octanoate β-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 the exchange of ATP for AMP or ADP, 2) the ABC transporter protein complex Pxa1p/Pxa2p, which mediates both uni-directional acyl-CoA and ATP uptake, and 3) the mitochondrial Aac2p protein, which catalyzes ATP/ADP exchange and has a dual localization in both mitochondria and peroxisomes. Our results provide compelling evidence for a complementary system for the uptake of ATP in peroxisomes.
过氧化物酶体是参与各种代谢过程的重要细胞器，包括脂肪酸β-氧化。它们的代谢功能需要代谢物和辅助因子（包括ATP）在过氧化物酶体膜上进行可控交换。我们研究了酵母中哪些蛋白质参与过氧化物酶体对ATP的摄取。使用野生型和靶向缺失菌株，我们测量了ATP依赖性过氧化物酶体辛酸β-氧化、使用过氧化物酶体靶向的ATP传感报告蛋白测量过氧化物酶体内的ATP水平，以及从纯化的过氧化物酶体制备的蛋白脂质体中的ATP摄取。我们表明，过氧化物酶体内的ATP水平由不同的过氧化物酶体膜蛋白维持，每种蛋白具有不同的作用模式：1）先前报道的Ant1p蛋白，它催化ATP与AMP或ADP的交换；2）ABC转运蛋白复合物Pxa1p/Pxa2p，它介导单向酰基辅酶A和ATP的摄取；3）线粒体Aac2p蛋白，它催化ATP/ADP交换，并且在线粒体和过氧化物酶体中都有双重定位。我们的结果为过氧化物酶体中ATP摄取的互补系统提供了有力证据。
