Jezek P, Krasinskaya I P, Smirnova I, Drahota Z
Institute of Physiology, Czechoslovak Academy of Sciences, Prague.
FEBS Lett. 1989 Jan 16;243(1):37-40. doi: 10.1016/0014-5793(89)81213-x.
A concerted function of purine nucleotide (PN) binding and fatty acid (FA) release from the uncoupling protein (UP) resulting in the maximum coupling (potential) of brown adipose tissue (BAT) mitochondria was demonstrated. The uncoupling effect of FA was studied (at 4 mM MgCl2): 17 nmol oleate per mg protein caused a slight uncoupling with 8.9 mM ATP but with ATP below 3.6 mM almost total uncoupling was achieved. This shows that the PN-controlled gate can be stabilized in the closed conformation (with 8.9 mM ATP), also when FA is bound to UP. The sensitivity of the FA effect to ATP proves that oleate directly interacts with UP. The closed conformation of the H+ channel of UP is then abolished by oleate when a lower free ATP concentration is maintained outside.
已证实嘌呤核苷酸（PN）结合与解偶联蛋白（UP）释放脂肪酸（FA）的协同作用可导致棕色脂肪组织（BAT）线粒体的最大偶联（电位）。研究了脂肪酸的解偶联作用（在4 mM MgCl2条件下）：每毫克蛋白质17 nmol油酸在8.9 mM ATP时引起轻微解偶联，但在ATP低于3.6 mM时几乎实现完全解偶联。这表明，即使脂肪酸与解偶联蛋白结合，PN控制的门也可以稳定在关闭构象（8.9 mM ATP时）。脂肪酸效应对ATP的敏感性证明油酸直接与解偶联蛋白相互作用。当外部维持较低的游离ATP浓度时，油酸会消除解偶联蛋白H+通道的关闭构象。
