泄漏的核糖体扫描使绿藻中可调节的二基斯特龙ORF的翻译成为可能
Marco A Dueñas1, Rory J Craig2, Sean D Gallaher2
1Department of Plant and Microbial Biology, University of California, Berkeley, CA 94720.
概括
绿藻使用泄漏的核糖体扫描来从单个二基斯特龙信使RNA (mRNA) 转换多种蛋白质. 修改第一个开放的读取 (ORF 1) 的翻译信号,细调下游ORF的表达.
科学领域:
- 分子生物学分子生物学
- 遗传学 遗传学 是一个
- 生物信息学是一种生物信息学.
背景情况:
- 以前被认为是罕见的核编码多基斯特龙越来越多地被发现.
- 在绿藻中,多基斯特龙转录是常见的,但翻译机制尚不清楚.
研究的目的:
- 在绿藻中研究二基斯特龙信使RNA (mRNA) 翻译的机制.
- 为了评估竞争的模型,多个多是如何从单个转录翻译的.
主要方法:
- 在*Chlamydomonas reinhardtii*和*Auxenochlorella protothecoides**中对精选的双基位进行生物信息分析.
- 在A. protothecoides*中的体内突变分析.
- 构建和测试一个合成的双电波双报道系统.
主要成果:
- 双基位表现为第一个开放的读取 (ORF 1) 的弱的Kozak样序列和ORF 2的几个上游启动编码.
- 突变ORF 1的Kozak样序列在体内改变了ORF 2的记者表达.
- 一个合成记者显示了ORF 1和ORF 2的反向调节表达,基于ORF 1的科扎克式序列强度.
结论:
- 多个ORF的翻译在绿藻二基斯特罗尼克转录中通过ORF 1的插曲性泄漏扫描发生.
- 这种机制对理解真核细胞上游开放阅读框架 (uORF) 和合成生物学应用有影响.
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