Identification of uncharacterized proteins potentially localized to mitochondria (UPMs) in <scp> <i>Saccharomyces cerevisiae</i> </scp> using a fluorescent protein unstable in the cytoplasm
Identification of uncharacterized proteins potentially localized to mitochondria (UPMs) in <scp> <i>Saccharomyces cerevisiae</i> </scp> using a fluorescent protein unstable in the cytoplasm
复制标题
使用细胞质中不稳定的荧光蛋白鉴定<scp> <i>酿酒酵母</i> </scp>中可能定位于线粒体（UPM）的未表征蛋白
作者：
Horiuchi Satoshi;Namba Shotaro;Saeki Nozomu;Satoh Ayano;Moriya Hisao
真核细胞是由细胞器组成的，每个细胞器都含有在其功能中发挥作用的蛋白质。因此，蛋白质的定位，特别是细胞器的定位，是推断该蛋白质功能的线索。在这项研究中，我们试图利用一种在细胞质中快速降解的荧光蛋白(GFPdeg)来鉴定出芽酵母中新的线粒体定位蛋白。在预测工具Deeploc-1.0预测定位到线粒体的发芽酵母蛋白中，排除了已知的线粒体定位或功能相关的蛋白，并选择了95个功能未知的蛋白进行分析。通过强制表达GFPdeg融合蛋白和观察它们的定位，我们鉴定了35个可能定位于线粒体(UPMS)的未鉴定蛋白质，其中包括8个已鉴定的定位于线粒体的蛋白质。其中大多数没有N端的线粒体定位信号，是进化上年轻的“新兴基因”，只存在于酿酒酵母中。这些基因中的一些被发现在线粒体发育的后伸长转换阶段上调，这表明它们实际上参与了线粒体的某些功能。
Eukaryotic cells are composed of organelles, and each organelle contains proteins that play a role in its function. Therefore, the localization of a protein, especially to organelles, is a clue to infer the function of that protein. In this study, we attempted to identify novel mitochondrially localized proteins in the budding yeastSaccharomyces cerevisiaeusing a fluorescent protein (GFPdeg) that is rapidly degraded in the cytoplasm. Of the budding yeast proteins predicted to localize to mitochondria by the prediction tool Deeploc‐1.0, those with known mitochondrial localization or functional relevance were eliminated, and 95 proteins of unknown function were selected as candidates for analysis. By forced expression of GFPdeg fusion proteins with these proteins and observation of their localization, we identified 35 uncharacterized proteins potentially localized to mitochondria (UPMs) including 8 previously identified proteins that localize to mitochondria. Most of these had no N‐terminal mitochondrial localization signal and were evolutionarily young “emerging genes” that exist only inS.cerevisiae. Some of these genes were found to be upregulated during the postdiauxic shift phase when mitochondria are being developed, suggesting that they are actually involved in some mitochondrial function.