Leighton J, Schatz G
Department of Biochemistry, University of Basel, Switzerland.
EMBO J. 1995 Jan 3;14(1):188-95. doi: 10.1002/j.1460-2075.1995.tb06989.x.
In an attempt to identify a mitochondrial ATP binding cassette (ABC) transporter, we have used the polymerase chain reaction to amplify 10 DNA fragments homologous to members of the ABC family from the yeast Saccharomyces cerevisiae. We disrupted five of the corresponding genes and found that one of the resulting null mutants barely grew on rich medium and failed to grow on minimal medium. This gene, termed ATM1, encodes a putative 'half-transporter' of 694 amino acids. Atm1p is synthesized with an N-terminal mitochondrial matrix-targeting signal and is located in the mitochondrial inner membrane, with its C-terminal ATPase domain exposed to the matrix. Cells lacking a functional ATM1 gene have an unstable mitochondrial genome and have white mitochondria that completely lack cytochromes. Atm1p is the first mitochondrial member of the ABC family to be identified and the only eukaryotic ABC transporter that has been shown to be necessary for normal cellular growth.
为了鉴定一种线粒体ATP结合盒（ABC）转运蛋白，我们利用聚合酶链反应从酿酒酵母中扩增出10个与ABC家族成员同源的DNA片段。我们破坏了其中5个相应的基因，发现其中一个产生的缺失突变体在丰富培养基上几乎无法生长，在基本培养基上则不能生长。这个基因被称为ATM1，编码一个推定的由694个氨基酸组成的“半转运蛋白”。Atm1p在合成时带有一个N端线粒体基质靶向信号，位于线粒体内膜，其C端ATP酶结构域暴露于基质中。缺乏功能性ATM1基因的细胞具有不稳定的线粒体基因组，并且其白色线粒体完全缺乏细胞色素。Atm1p是被鉴定出的ABC家族的首个线粒体成员，也是唯一一种已被证明对正常细胞生长必不可少的真核ABC转运蛋白。
