Photoaffinity labelling of the mitochondrial uncoupling protein by [3H]azido fatty acid affects the anion channel

FEBS Letters

Hanuš, Jan²  Borecký, Jiří¹  Růžička, Michal¹  Ježek, Petr¹ 

[1] Institute of Physiology, Department No. 375, Membrane Transport Biophysics, Academy of Sciences of the Czech Republic, Vídeňská 1083, CZ 14220 Prague, Czech Republic;Institute of Experimental Botany, Isotope Laboratory, Academy of Sciences of the Czech Republic, Videňská 1083, CZ 14220 Prague, Czech Republic

关键词: Uncoupling protein;    Photoaffinity labelling;    Azido fatty acid;    Fatty acid;    [3H]AzDA;    12-(4-azido-2-nitrophenylamino)-[3H]dodecanoic acid;    [3H]AzHA;    16-(4-azido-2-nitrophenylamino)[3H4]hexadecanoic acid;    BAT;    brown adipose tissue;    BSA;    bovine serum albumin;    FA;    fatty acid;    MOPS;    3-(N-morpholino)propanesulfonic acid;    Octyl-POE;    octylpentaoxyethylene;    UcP;    uncoupling protein;   

DOI  :  10.1016/0014-5793(96)00161-5

学科分类：生物化学/生物物理

来源: John Wiley & Sons Ltd.

【 摘 要 】

Brown adipose tissue (BAT) mitochondria were incubated with the azido derivative of fatty acid (hexadecanoic) containing four tritium atoms, [³H]AzHA, and among all mitochondrial proteins only a few proteins were photolabelled after irradiation with UV. It suggests the existence of specific fatty acid binding sites on mitochondrial proteins. It was also possible to label with [³H]AzHA the isolated uncoupling protein (UcP) of BAT mitochondria with a low stoichiometry — lower than one AzHA per dimeric UcP. These results together with the observed competition (i.e. prevention of photolabelling) of various UcP anionic substrates with [³H]AzHA and its dodecanoic acid analogue, suggest the existence of the specific fatty acid binding site on UcP identical with the anion channel or anion translocating site.

【 授权许可】

Unknown