The subcellular localization of a protein is important for its proper function. Escherichia coli MinE is a small protein with clear subcellular localization, which provides a good model to study protein localization mechanism. In the present study, a series of recombinant minEs truncated in one end or in the middle regions, fused with egfp, was constructed, and these recombinant proteins could compete to function with the chromosomal MinE. Our results showed that the sequences related to the subcellular localization of MinE span several functional domains, demonstrating that MinE positioning in cells depends on multiple factors. The eGFP fusions with some truncated MinE from N-terminal resulted in different cell phenotypes and localization features, implying that these fusions can interfere chromosomal MinE’s function, similar to MinE^36–88 phenotype in the previous report. The amino acid in the region (32–48) is sensitive to change MinE conformation and influence its dimerization. Some truncated protein structure could be unstable. Thus, the MinE localization is prerequisite for its proper anti-MinCD function and some new features of MinE were demonstrated. This approach can be extended for subcellular localization research for other essential proteins.

中文翻译：

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通过竞争结合法在大肠杆菌中分析负责其亚细胞定位的MinE序列。

蛋白质的亚细胞定位对于其正常功能很重要。大肠杆菌MinE是一种具有清晰的亚细胞定位的小蛋白，为研究蛋白质的定位机理提供了一个很好的模型。在本研究中，与egfp融合的一系列重组minE在一端或中间区域被截短，构建了这些重组蛋白，它们可以与染色体MinE竞争功能。我们的结果表明，与MinE的亚细胞定位相关的序列跨越了几个功能域，这表明MinE在细胞中的定位取决于多种因素。eGFP与N端一些截短的MinE融合导致不同的细胞表型和定位特征，这意味着这些融合可以干扰染色体MinE的功能，类似于MinE ^36-88表型在以前的报告中。该区域（32-48）中的氨基酸对改变MinE构象敏感，并影响其二聚化。某些截短的蛋白质结构可能不稳定。因此，MinE本地化是其适当的抗MinCD功能的前提，并证明了MinE的一些新功能。这种方法可以扩展到其他必需蛋白质的亚细胞定位研究。