Počet záznamů: 1
Activating omega-6 polyunsaturated fatty acids and inhibitory purine nucleotides are high affinity ligands for novel mitochondrial uncoupling proteins UCP2 and UCP3
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SYSNO ASEP 0142484 Druh ASEP J - Článek v odborném periodiku Zařazení RIV J - Článek v odborném periodiku Poddruh J Ostatní články Název Activating omega-6 polyunsaturated fatty acids and inhibitory purine nucleotides are high affinity ligands for novel mitochondrial uncoupling proteins UCP2 and UCP3 Tvůrce(i) Žáčková, Markéta (FGU-C)
Škobisová, Eva (FGU-C)
Urbánková, Eva (FGU-C)
Ježek, Petr (FGU-C) RID, ORCIDZdroj.dok. Journal of Biological Chemistry. - : Elsevier - ISSN 0021-9258
Roč. 278, č. 23 (2003), s. 20761-20769Poč.str. 9 s. Jazyk dok. eng - angličtina Země vyd. US - Spojené státy americké Klíč. slova uncoupling protein-2 ; polyunsaturated fatty acids ; recombinant yeast expression Vědní obor RIV CE - Biochemie CEP IAA5011106 GA AV ČR - Akademie věd GA301/02/1215 GA ČR - Grantová agentura ČR ME 389 GA MŠMT - Ministerstvo školství, mládeže a tělovýchovy CEZ AV0Z5011922 - FGU-C Anotace Human UCP2 and UCP3, expressed in yeast, were studied to establish their high affinity regulatory ligands. UCPn were reconstituted into liposomes and assayed for fatty acid (FA)-induced H+ efflux. All natural long chain FAs activated UCP2- and UCP3-mediated H+ translocation. Coenzyme Q10 had no further significant activating effect. Evaluated parameters of FA activation (FA cycling) kinetics revealed the highest apparent affinity to UCP2 for omega-6 polyunsaturated FAs (PUFAs), all-cis-8,11,14-eicosatrienoic and all-cis-6,9,12-octadecatrienoic acids, which are also the most potent agonists of the nuclear PPAR-beta receptor in the activation of UCP2 transcription. Omega-3 PUFA, cis-5,8,11,14,17-eicosapentaenoic acid had lower affinity. Although being omega-6 PUFA, arachidonic acid exhibited the same low affinity as lauric acid. These findings suggest a possible dual role of some PUFAs in activating both, UCPn expression and uncoupling activity. UCP2(UCP3)-dependent H+ translocation activated by all tested FAs was inhibited by purine nucleotides with apparent affinity to UCP2 (reciprocal Ki) decreasing in order: ADP > ATP ~ GTP > GDP >> AMP. Also 3H-GTP (3H-ATP) binding to isolated E.coli or yeast-expressed UCP2 or UCP3 exhibited high affinity, similar to UCP1. The estimated number of 3H-GTP high affinity binding sites was (in pmols/mg protein) 182 in lung mitochondria; 74 in kidney; 28 in skeletal muscle; and ~20 in liver mitochondria. We conclude that purine nucleotides must be the physiological inhibitors of the UCPn-mediated uncoupling in vivo. Pracoviště Fyziologický ústav Kontakt Lucie Trajhanová, lucie.trajhanova@fgu.cas.cz, Tel.: 241 062 400 Rok sběru 2004
Počet záznamů: 1