拟南芥中一个未知功能蛋白的叶绿体亚细胞定位研究

Study of Subcellular Localization of the Expressed Protein in Arabidopsis thaliana

生物信息学分析表明,模式植物拟南芥叶绿体中含有大约4000多种蛋白质,目前只分离得到1000多种,其他预测的叶绿体蛋白的实验验证对叶绿体功能研究有重要意义。本文对一个预测的叶绿体未知功能蛋白AT5G48790进行了亚细胞定位研究。我们克隆了该基因5'端长178bp的DNA片段,与绿色荧光蛋白(GFP)基因构建重组载体pMON530-cTP-GFP。转基因植株通过激光共聚焦显微镜观察,GFP只在叶绿体中特异表达。实验结果表明,AT5G48790的确为叶绿体蛋白。本实验方法也可用于其他预测的蛋白质的实验验证。

Bioinformatics analysis has revealed about 4 000 proteins in chloroplasts; however, only about 1 000 proteins have been validated. Thus, we established an experimental system to verify predicted chloroplast proteins. AtSg48790 was predicted to be an Arabidopsis chloroplast protein. The 178 bp segment of the 5＇ sequence of this gene was cloned and fused with GFP to construct a binary vector pMON530-cTP-GFP for genetic transformation. On confocal laser-scanning microscopy, green fluorescent signals were localized in chloroplasts in transgenic Arabidopsis plants. The results suggest that At5g48790 encodes a chloroplast protein. This experiment can also be used to investigate other proteins predicted to be located in chloroplasts in Arabidopsis.