肽链释放因子和核糖体蛋白L11在八肋游仆虫细胞中的定位

Localization of polypeptides release factors and ribosome protein L11 in Euplotes octocarinatus

摘要:

原生动物纤毛虫是一类单细胞真核生物，其蛋白质合成终止过程中密码子使用的特殊性使其成为研究蛋白质合成终止机制的一个经典模型。为了能够有效地分析生物大分子在该细胞中的功能作用位点，本研究根据该生物染色体结构的特征，构建了含有红色荧光蛋白的大核人工染色体EoMAC_R，并与之前构建的含绿色荧光的大核染色体EoMAC_G一起，对蛋白质合成终止有关的3个重要因子核糖体大亚基蛋白L11、多肽链释放因子eRF1和eRF3在八肋游仆虫细胞中进行了荧光共定位分析。结果显示，在八肋游仆虫细胞中，蛋白质翻译过程主要位于“C”形大核内侧区域。构建的人工染色体能够作为一种有效的工具，对目的蛋白质在八肋游仆虫细胞中进行定位分析。

Abstract:

Protozoan ciliates are a group of unicellular eukaryotes. The special characteristics of stop codons usage in termination of protein biosynthesis in ciliates cells makes them an ideal model to study the mechanism of stop codon recognition of polypeptides release factors. To localize the functional positions of biomolecules in ciliates cell, we constructed a macronuclear artificial chromosome containing a gene encoding red fluorescence protein (EoMAC_R) based on the structural characteristics of ciliates chromosome. Three factors, L11, eRF1a, and eRF3 that are involved in termination process of protein synthesis were colocalized in Euplotes octocarinatus cells by using novel EoMAC_R and the previously constructed EoMAC_G. The results indicated that protein synthesis mainly occurred inside the “C” shape macronucleus, suggesting that EoMAC could be a useful tool for localizing biomolecules in ciliates cell.