The mitochondrial uncoupling proteins.
The mitochondrial uncoupling proteins.
复制标题
线粒体解偶联蛋白。
DOI：
10.1186/gb-2002-3-12-reviews3015
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发表时间：
2002
期刊：
影响因子：
12.3
通讯作者：
Rial E
中科院分区：
文献类型：
--
作者：
Ledesma A;de Lacoba MG;Rial E
解偶联蛋白是存在于线粒体内膜中的转运蛋白，介导呼吸链产生的质子梯度的受控释放，以发挥生热、维持氧化还原平衡或减少活性氧产生等功能。解偶联蛋白 (UCP) 是存在于线粒体内膜中的转运蛋白，可调节呼吸链产生的质子梯度的释放。这种能量耗散机制可以起到产热、维持氧化还原平衡或减少活性氧产生等功能。然而，一些 UCP 同系物可能无法充当真正的解偶联剂，并且它们的活性尚未确定。 UCP是完整的膜蛋白，每个分子量为31-34 kDa，具有三联结构，其中约100个残基的区域重复3次；每个重复编码两个跨膜片段和一个长亲水环。功能性载体单元是同型二聚体。迄今为止，已描述了编码UCP家族成员的45个基因，它们可分为6个家族。大多数所描述的基因来自哺乳动物，但 UCP 基因也在鱼类、鸟类和植物中发现，并且也有功能证据表明它们存在于真菌和原生动物中。 UCP 的成熟形式由核基因编码，与许多核编码的线粒体蛋白不同，它们缺乏可裂解的线粒体输入信号。线粒体靶向的信息存在于突入线粒体基质的第一个环中；第二个基质环对于将蛋白质插入线粒体内膜至关重要。 UCP 在转录水平以及线粒体的激活和抑制方面受到调节。
The uncoupling proteins are transporters, present in the mitochondrial inner membrane, that mediate a regulated discharge of the proton gradient that is generated by the respiratory chain, to serve functions such as thermogenesis, maintenance of the redox balance, or reduction in the production of reactive oxygen species. The uncoupling proteins (UCPs) are transporters, present in the mitochondrial inner membrane, that mediate a regulated discharge of the proton gradient that is generated by the respiratory chain. This energy-dissipatory mechanism can serve functions such as thermogenesis, maintenance of the redox balance, or reduction in the production of reactive oxygen species. Some UCP homologs may not act as true uncouplers, however, and their activity has yet to be defined. The UCPs are integral membrane proteins, each with a molecular mass of 31-34 kDa and a tripartite structure in which a region of around 100 residues is repeated three times; each repeat codes for two transmembrane segments and a long hydrophilic loop. The functional carrier unit is a homodimer. So far, 45 genes encoding members of the UCP family have been described, and they can be grouped into six families. Most of the described genes are from mammals, but UCP genes have also been found in fish, birds and plants, and there is also functional evidence to suggest their presence in fungi and protozoa. UCPs are encoded in their mature form by nuclear genes and, unlike many nuclear-encoded mitochondrial proteins, they lack a cleavable mitochondrial import signal. The information for mitochondrial targeting resides in the first loop that protrudes into the mitochondrial matrix; the second matrix loop is essential for insertion of the protein into the inner mitochondrial membrane. UCPs are regulated at both the transcriptional level and by activation and inhibition in the mitochondrion.