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在酵母逆转子 Ty:tRNAs 诱导 7 核酸最小位点上的滑动
1Department of Microbiology University of Connecticut Health Center Farmington 06032.
Cell
|July 27, 1990
概括
酵母逆转移子TYB基因表达是由核糖体框架转移调节的. 一个保存的7核酸序列,CUU-AGG-C,对于这个过程至关重要,涉及特定的tRNA和定向移.
科学领域:
- 分子生物学分子生物学
- 遗传学 是一个遗传学.
- 生物化学 生物化学
背景情况:
- 核糖体框架转移是一个关键的机制,调节基因表达在真核细胞逆转移体.
- 之前的研究发现了酵母中的14核酸序列 Ty元素对于核糖体框架转移至关重要.
- 已知酵母 Ty 逆转移体的 TYB 基因受到这种框架转移事件的调节.
研究的目的:
- 在酵母 Ty 逆转移体中确定有效的核糖体框架转移所需的最小序列.
- 阐明特定的tRNA和子序列在移机制中的作用.
- 为了研究相对于启动码的框架移动的方向性和位置效应.
主要方法:
- 序列分析以确定用于移的必要核酸.
- 位点定向的突变发生改变了保存的序列.
- 测试tRNA过度产生的实验,以评估tRNA可用性的影响.
- 分析不同位置相对于起始代码的移效率.
主要成果:
- 一个最小的7核酸序列 (CUU-AGG-C) 足以达到正常水平的核糖体框架转移.
- 对CUU-AGG-C序列的改变显著降低了移效率.
- 有证据表明tRNA (UAGLeu) 和tRNA (CCUArg) 在移事件中参与.
- 移是定向的,读取特定的,并且对从启动编码子的距离敏感.
结论:
- CUU-AGG-C动机对于Ty1核糖体框架转移至关重要,可能通过特定的tRNA相互作用.
- 由于有限的tRNA (CCUArg) 可用性导致的转化暂停会诱导由tRNA (UAGLeu) 介导的移.
- 相对于起始编码子,引发移序列的精确定位会影响过程的效率.
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