Functional characterization of the mitochondrial uncoupling proteins from the white shrimp Litopenaeus vannamei
Por:
Mendez-Romero, Ofelia, Rodriguez-Armenta, Chrystian, Uribe-Carvajal, Salvador, Muhlia-Almazan, Adriana
Publicada:
1 ene 2020
Resumen:
Mitochondrial uncoupling proteins (UCPs) play an essential role in dissipating the proton gradient and controlling the mitochondrial inner membrane potential. When active, UCPs promote proton leak across the inner membrane, oxidative phosphorylation uncoupling, oxygen uptake increase and decrease the ATP synthesis. Invertebrates possess only isoforms UCP4 and UCP5, however, the role of these proteins is not clear in most species since it may depend on the physiological needs of each animal. This study presents the first functional characterization of crustacean uncoupling proteins from the white shrimp Litopenaeus vannamei LvUCP4 and LvUCP5. Free radicals production in various shrimp organs/tissues was first evaluated, and mitochondria were isolated from shrimp pleopods. The oxygen consumption rate, membrane potential and proton transport of the isolated non-phosphorylating mitochondria were used to determine LvUCPs activation/inhibition. Results indicate that UCPs activity is stimulated in the presence of 4-hydroxyl-2-nonenal (HNE) and myristic acid, and inhibited by the purine nucleotide GDP. A hypoxia/re-oxygenation assay was conducted to determine whether UCPs participate in shrimp mitochondria response to oxidative stress. Isolated mitochondria from shrimp at re-oxygenation produced large quantities of hydrogen peroxide and higher levels of both LvUCPs were immunodetected. Results suggest that, besides the active response of the shrimp antioxidant system, UCP-like activity is activated after hypoxia exposure and during re-oxygenation. LvUCPs may represent a mild uncoupling mechanism, which may be activated before the antioxidant system of cells, to early control reactive oxygen species production and oxidative damage in shrimp. © 2020 Elsevier B.V.
Filiaciones:
Bioenergetics and Molecular Genetics Lab, Centro de Investigacion en Alimentacion y Desarrollo, A. C. Carretera Gustavo Astiazaran Rosas 36, Hermosillo, Sonora 83304, Mexico
Department of Molecular Genetics, Instituto de Fisiologia Celular, Universidad Autonoma de Mexico, Ciudad Universitaria, PO Box 70-242, Mexico City, Mexico
Ctr Invest Alimentac & Desarrollo, Bioenerget & Mol Genet Lab, AC Carretera Gustavo Astiazaran Rosas 36, Hermosillo 83304, Sonora, Mexico
Univ Autonoma Mexico, Inst Fisiol Celular, Dept Mol Genet, Ciudad Univ,POB 70-242, Mexico City, DF, Mexico
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