Chloupková Maja, Reaves Scott K, LeBard Linda M, Koeller David M
Department of Pediatrics, Oregon Health and Science University, Portland, OR 97239, USA.
FEBS Lett. 2004 Jul 2;569(1-3):65-9. doi: 10.1016/j.febslet.2004.05.051.
The ATP-binding cassette (ABC) transporters constitute one of the largest families of proteins in evolution. The ATM1 gene of the yeast Saccharomyces cerevisiae encodes an ABC protein, which is localized to the mitochondrial inner membrane. A deletion of ATM1 results in the accumulation of up to a 30-fold excess of mitochondrial iron, loss of mitochondrial cytochromes and abnormalities of cytosolic iron metabolism. In this study, we have evaluated the role of conserved sequence elements in Atm1p in its function and dimerization in vivo. We report that conserved residues in the Walker A and B motifs of the nucleotide binding domain, which are required for ATP binding and hydrolysis, are essential for Atm1p function. In addition, we provide evidence that ATP binding is important for Atm1p dimerization.
ATP结合盒（ABC）转运蛋白是进化过程中最大的蛋白质家族之一。酿酒酵母的ATM1基因编码一种ABC蛋白，该蛋白定位于线粒体内膜。ATM1基因缺失会导致线粒体铁积累高达30倍，线粒体细胞色素丧失以及胞质铁代谢异常。在本研究中，我们评估了Atm1p中保守序列元件在其体内功能和二聚化中的作用。我们报告，核苷酸结合域的沃克A和B基序中的保守残基是ATP结合和水解所必需的，对Atm1p功能至关重要。此外，我们提供证据表明ATP结合对Atm1p二聚化很重要。
