Laboratory of Biochemistry and Molecular Biology, Department of Pharmaco-Biology, University of Bari, Via Orabona 4, 70125 Bari, Italy.
Plant J. 2011 Apr;66(1):161-81. doi: 10.1111/j.1365-313X.2011.04516.x.
The mitochondrial carriers (MC) constitute a large family (MCF) of inner membrane transporters displaying different substrate specificities, patterns of gene expression and even non-mitochondrial organelle localization. In Arabidopsis thaliana 58 genes encode these six trans-membrane domain proteins. The number in other sequenced plant genomes varies from 37 to 125, thus being larger than that of Saccharomyces cerevisiae and comparable with that of Homo sapiens. In addition to displaying highly similar secondary structures, the proteins of the MCF can be subdivided into subfamilies on the basis of substrate specificity and the presence of specific symmetry-related amino acid triplets. We assessed the predictive power of these triplets by comparing predictions with experimentally determined data for Arabidopsis MCs, and applied these predictions to the not yet functionally characterized mitochondrial carriers of the grass, Brachypodium distachyon, and the alga, Ostreococcus lucimarinus. We additionally studied evolutionary aspects of the plant MCF by comparing sequence data of the Arabidopsis MCF with those of Saccharomyces cerevisiae and Homo sapiens, then with those of Brachypodium distachyon and Ostreococcus lucimarinus, employing intra- and inter-genome comparisons. Finally, we discussed the importance of the approaches of global gene expression analysis and in vivo characterizations in order to address the relevance of these vital carrier proteins.
线粒体载体（MC）构成了一个庞大的家族（MCF），由具有不同底物特异性、基因表达模式甚至非线粒体细胞器定位的内膜转运蛋白组成。在拟南芥中，有 58 个基因编码这些六跨膜域蛋白。在其他已测序的植物基因组中，该数字从 37 到 125 不等，因此大于酿酒酵母，与人类相当。除了显示高度相似的二级结构外，MCF 的蛋白质还可以根据底物特异性和特定对称相关氨基酸三肽的存在进行亚家族划分。我们通过将预测与拟南芥 MC 的实验确定数据进行比较来评估这些三肽的预测能力，并将这些预测应用于尚未进行功能表征的草类植物短柄草和藻类微拟球藻的线粒体载体。我们还通过比较拟南芥 MCF 的序列数据与酿酒酵母和人类的序列数据，然后与短柄草和微拟球藻的序列数据进行比较，采用基因组内和基因组间比较，研究了植物 MCF 的进化方面。最后，我们讨论了进行全局基因表达分析和体内表征的重要性，以解决这些重要载体蛋白的相关性。
