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 Duenas1, Rory J Craig2, Sean D Gallaher2,3
1Department of Plant and Microbial Biology, University of California Berkeley, University of California, Berkeley, CA 94720, USA.
bioRxiv : the preprint server for biology
|August 2, 2024
概括
绿藻使用漏洞扫描机制从单个基因转录中翻译多个蛋白质. 这个过程涉及到第一个开放式读取 (ORF) 的核糖体扫描,以使后续的ORFs的翻译.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 藻类生物学 藻类生物学
背景情况:
- 以前被认为是罕见的核编码多基因基因,由于测序的进步,越来越多地被确定.
- 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:
- 为了研究绿藻中多晶基因表达的机制.
- 评估竞争的模型,从单个成绩单翻译多个开放阅读框架 (ORFs).
主要方法:
- 从*克拉米多马纳斯强硬菌*和*奥克斯诺克洛雷拉原始菌*手工精选的双基斯特朗基位点进行生物信息分析.
- 在*Auxenochlorella protothecoides*中进行体内突变分析,以测试泄漏的扫描模型.
- 构建一个合成的双电波双记者系统.
主要成果:
- 双基斯特罗尼基位点对第一个ORF (ORF 1) 的弱Kozak类序列有偏好,并且在ORF 2之前对上游启动密码子的代表性不足.
- 在体内对ORF 1 Kozak-like序列的突变影响了ORF 2的记者表达,较弱的序列增强了它.
- 一个合成记者证明了基于ORF 1 Kozak-like序列强度的两个蛋白质的反向调节表达.
结论:
- 在绿藻中,多基斯特罗尼克转录的翻译与ORF 1的偶尔泄漏的核糖体扫描一致.
- 这种机制允许下游ORF的翻译.
- 这些发现对理解真核细胞上游开放阅读框架以及合成生物学应用有意义.
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