SYSTEMATIC ALTERATIONS IN THE ANTICODON ARM MAKE TRANSFER RNAGLU-SUOC A MORE EFFICIENT SUPPRESSOR
SYSTEMATIC ALTERATIONS IN THE ANTICODON ARM MAKE TRANSFER RNAGLU-SUOC A MORE EFFICIENT SUPPRESSOR
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DOI：
10.1002/j.1460-2075.1987.tb02392.x
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发表时间：
1987-05-01
期刊：
影响因子：
11.4
通讯作者：
YARUS, M
中科院分区：
文献类型：
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作者：
RAFTERY, LA;YARUS, M
使用位点特异性诱变，我们构建了五个更有效的变体tRNAGlu-Suoc，一个非常低效的赭石抑制。每个变体都有一个延长的反密码子，或反密码子臂的区域，这与翻译密码子Uxx的正常tRNA中发现的更相似。抑制效率总是增加与扩展的反密码子的一个正常的Uxx翻译tRNA的相似性。螺旋和环中的改变的核苷酸强烈影响效率，没有位置依赖性，取代之间没有显著的相互作用。具有所有取代的变体比亲本tRNAGlu-Suoc有效230倍（在一种情况下）。另外两个意想不到的变体似乎是“上下文突变体”，改变了对消息上下文的响应。
Using site-specific mutagenesis, we constructed five more efficient variants of tRNAGlu-Suoc, an extremely inefficient ochre suppressor. Each variant has an extended anticodon, or region of the anticodon arm, which is more similar to that found in normal tRNAs which translate codons Uxx. Suppressor efficiency invariably increases with similarity of the extended anticodon to that of a normal Uxx-translating tRNA. Altered nucleotides in both helix and loop strongly affect efficiency, with no position dependence and no significant interaction between substitutions. The variant with all substitutions is 230-fold more efficient (in one context) than the parental tRNAGlu-Suoc. Two other unexpected variants seem to be ''context mutants'', having altered response to message context.