Identification of a role for actin in translational fidelity in yeast.
Identification of a role for actin in translational fidelity in yeast.
复制标题
鉴定肌动蛋白在酵母翻译保真度中的作用。
DOI：
10.1007/s00438-002-0726-x
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发表时间：
2002
期刊：
影响因子：
--
通讯作者：
Adams,AEM
中科院分区：
文献类型：
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作者：
Kandl,KA;Munshi,R;Ortiz,PA;Andersen,GR;Kinzy,TG;Adams,AEM
许多研究表明肌动蛋白在翻译中发挥作用，但该作用的分子细节尚不清楚。为了阐明肌动蛋白在翻译中的功能，我们研究了 25 个等基因条件酵母肌动蛋白突变体。引人注目的是，对这些突变体的分析表明，所有测试的突变体均不存在因蛋白质合成速率降低而导致的条件性生长缺陷。对 latrunculin A 处理的野生型细胞的分析表明，即使肌动蛋白细胞骨架完全破坏，对翻译速率也没有显着影响。然而，通过对 25 个肌动蛋白突变对翻译抑制剂的保真度和敏感性的影响的分析，发现了两个突变（act1-2 和 act1-122）会导致翻译保真度显着降低（通过无义抑制进行测定），以及几个对巴龙霉素敏感的突变体，这会影响翻译保真度。翻译延伸因子 1A (eEF1A) 也在保真度中发挥作用，在过量 eEF1A 存在的情况下，四种突变体（act1-2、act1-20、act1-120 和 act1-125）对巴龙霉素更加敏感，而一种突变体 (act1-122) 变得不太敏感。总之，这些发现表明肌动蛋白可能对翻译速度并不重要，但可能在确保翻译保真度方面发挥关键作用。
Numerous studies have suggested a role for actin in translation, but the molecular details of this role are unknown. To elucidate the function(s) of actin in translation, we have studied 25 isogenic, conditional yeast actin mutants. Strikingly, analysis of these mutants indicates that none of those tested have conditional growth defects caused by reduced rates of protein synthesis; and analysis of latrunculin A-treated wild-type cells indicates that even complete disruption of the actin cytoskeleton has no significant effect on the rate of translation. However, analysis of the effect of the 25 actin mutations on fidelity and sensitivity to translation inhibitors identified two mutations (act1-2andact1-122) that cause a significant reduction in the fidelity of translation, as assayed by nonsense suppression, and several mutants that are sensitive to paromomycin, which affects translational fidelity. Translation elongation factor 1A (eEF1A) also has a role in fidelity, and in the presence of excess eEF1A four of the mutants (act1-2,act1-20,act1-120, andact1-125) are even more sensitive to paromomycin, while one mutant (act1-122) becomes less sensitive. Together, these findings suggest that actin may not be important for therateof translation, but may have a critical role in ensuring translational fidelity.