Klingenberg M, Winkler E, Echtay K
Institute of Physical Biochemistry, University of Munich, Schillerstrasse 44, D-80336 Munich, Germany.
Biochem Soc Trans. 2001 Nov;29(Pt 6):806-11. doi: 10.1042/0300-5127:0290806.
The biochemical functions of uncoupling proteins (UCPs) are discussed with the view of UCP1 as a paradigm. In contrast with UCP1, the heterologous expression of UCP3 in yeast is found to result primarily in extra-mitochondrial deposits and thus is unsuitable for studying UCP3 function. On expression in Escherichia coli inclusion bodies, UCPs extracted and incorporated into vesicles showed no H(+) transport, only Cl(-) transport. Only after addition of coenzyme Q was fully nucleotide-sensitive high-H(+) transport reconstituted, with UCP1 as well as with UCP2 and UCP3. The newly discovered cofactor role of coenzyme Q in H(+) transport is proposed to imply co-operation with fatty acids for the injection of H(+) into the UCP channel.
以解偶联蛋白1（UCP1）作为范例来讨论解偶联蛋白（UCPs）的生化功能。与UCP1不同，研究发现UCP3在酵母中的异源表达主要导致线粒体外沉积，因此不适合用于研究UCP3的功能。在大肠杆菌包涵体中表达后，提取并整合到囊泡中的UCPs没有表现出H(+)转运，仅表现出Cl(-)转运。只有在添加辅酶Q后，UCP1以及UCP2和UCP3才重新构建出对核苷酸完全敏感的高效H(+)转运。辅酶Q在H(+)转运中新发现的辅因子作用被认为意味着它与脂肪酸协同作用，将H(+)注入UCP通道。
