对AUG启动代码的功能分析揭示了新的保存序列,这些序列不利于真核细胞中mRNA的翻译
Greco Hernández1, Alejandra García1, Shira Weingarten-Gabbay2,3,4
1mRNA and Cancer Laboratory, Unit of Biomedical Research on Cancer, National Institute of Cancer (INCan), Mexico City 14080, Mexico.
Nucleic acids research
|December 1, 2023
概括
转化启动位点 (TIS) 背景在真核生物之间有所不同,保留了一个促进效率的-3A动机. 鉴定出了新型无菌的AUG上下文序列 (BACS),显著不利于翻译和影响基因本体学.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 单核生物基因表达的表达方式
背景情况:
- 对于精确的蛋白质合成,mRNA翻译启动位点 (TIS) 的选择至关重要.
- 脊椎动物研究发现了促进启动的特定TIS动机 (例如,-3 purin,+4 G).
- 在非脊椎动物真核生物中对TIS背景的实验分析仍然有限.
研究的目的:
- 在实验中分析TIS上下文位置 (-3, -2, -1, +4) 在多种类型的真核生物中的体外影响.
- 为了研究在小麦和酵母中哺乳动物科扎克图案的预测能力.
- 识别和描述调节翻译启动的新型序列元素.
主要方法:
- 在实验室分析子,Drosophila,小麦和酵母的mRNA序列.
- 在TIS位置 -3, -2, -1, +4.4的核酸的系统变化.
- 使用体外试验试验评估翻译效率.
- 保存序列的生物信息分析和基因本体学.
主要成果:
- 位于-3位置的纯氨酸,特别是氨酸 (-3A),在所有测试物种中始终提高了翻译效率.
- 在+4位置的最佳核酸在物种之间存在差异,表明特定环境的要求.
- 哺乳动物科扎克图案对小麦的预测价值很弱,对酵母来说基本上没有预测价值.
- 八个保存序列,称为荒的AUG上下文序列 (BACS),被确定为显著抑制翻译.
结论:
- 对于最佳的mRNA翻译的TIS环境显示出超出3A等保存元素的显著物种间变异.
- 荒的AUG上下文序列 (BACS) 代表了一类新定义的监管元素,它们积极不利于翻译启动.
- 对mRNA-核糖体复合体的结构分析为BACS功能提供了洞察力.
- 了解BACS和TIS的背景对于破译真核细胞基因调节和mRNA解码至关重要.
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