在植物中,AUG和非AUG三胞胎的翻译启动
Jhen-Cheng Fang1, Ming-Jung Liu2
1Biotechnology Center in Southern Taiwan, Academia Sinica, Tainan 711, Taiwan.
概括
植物使用许多超出标准AUG编码子的无注释翻译启动位点 (TIS). 了解这些替代TIS对于破译植物蛋白质组和注释大型植物基因组至关重要.
科学领域:
- 分子生物学分子生物学
- 基因组学就是基因组学.
- 植物科学 植物科学
背景情况:
- 在信使RNA (mRNA) 上精确选择翻译启动位点 (TIS) 对真核细胞蛋白质组调节对细胞信号的响应至关重要.
- 虽然正规翻译始于5'近位AUG编码子,但植物基因组包含许多未注释的替代AUG和非AUGTIS.
- 植物中这些普遍存在的,未注释的TIS的激活机制和生物学意义是一个活跃的研究领域.
研究的目的:
- 审查工厂TIS的选择机制,重点关注新发现的TIS.
- 讨论从植物中非AUG TIS开始的开放式读取框架 (ORF) 的生物特征.
- 探索cis调节性RNA元素和真核细胞启动因子 (eIF) 在TIS选择中的作用.
主要方法:
- 进行比较基因组学以识别未注释的TIS.
- 核糖体定位的全基因组概况.
- 对蛋白质N端末的分析最终证实了体内TIS使用.
主要成果:
- 许多未注释的AUG和非AUG TIS在植物中被使用.
- 非AUG TIS启动具有明显生物特征的新型开放阅读框架 (ORF).
- 无论是cis-regulatory RNA元素还是跨作用的eIF都会影响TIS选择.
结论:
- 没有注释的TIS代表了ORF的重要储备,这些ORF可以在各种条件下修改植物蛋白质组.
- 了解TIS选择机制对于准确的植物基因组功能注释至关重要,特别是在大型作物基因组中.
- 这些知识有助于理解植物的适应性和开发改进的作物品种.
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