Zuotin, a DnaJ molecular chaperone, stimulates cap-independent translation in yeast.
Zuotin, a DnaJ molecular chaperone, stimulates cap-independent translation in yeast.
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Zuotin 是一种 DnaJ 分子伴侣，可刺激酵母中不依赖帽子的翻译。
DOI：
10.1016/j.bbrc.2006.09.124
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发表时间：
2006
影响因子：
3.1
通讯作者：
Dasgupta,Asim
中科院分区：
文献类型：
--
作者：
Raychaudhuri,Santanu;Fontanes,Vanessa;Banerjee,Rajeev;Bernavichute,Yana;Dasgupta,Asim
从酵母中分离的小抑制RNA（IRNA）先前已被证明可以有效地阻断脊髓灰质炎病毒和丙型肝炎病毒IRES介导的翻译，通过隔离在帽非依赖性翻译中发挥重要作用的哺乳动物RNA结合（transacting）因子。在这里，我们已经调查了IRNA结合蛋白，可能参与在帽非依赖性翻译的酵母酿酒酵母。我们已经确定了Zuotin，一种类似于哺乳动物HSP-40分子伴侣的DnaJ分子伴侣蛋白，它与IRNA强烈相互作用。利用ZUO 1缺失的S. Zuo 1 p在酿酒酵母中的表达，证明了Zuo 1 p对由酵母TFIID mRNA 5′端非翻译区介导的帽非依赖性翻译的优先需求。利用zuo 1 ΔS进一步研究。补充了各种Zuo 1 p突变体的酿酒酵母表明Zuo 1 p的DnaJ结构域，已知影响其与HSP-70的相互作用，显着影响帽非依赖性翻译。这些结果首次证明了一个既定的伴侣蛋白在细胞mRNA的帽非依赖性翻译中的作用。
A small inhibitor RNA (IRNA) isolated from yeast has previously been shown to efficiently block poliovirus and hepatitis C virus IRES-mediated translation by sequestering mammalian RNA-binding (transacting) factors that play important roles in cap-independent translation. Here we have investigated the IRNA-binding proteins that might be involved in cap-independent translation in the yeast Saccharomyces cerevisiae. We have identified Zuotin, a DnaJ chaperone protein similar to mammalian HSP-40 chaperone, which interacts strongly with IRNA. Using ZUO1-deleted S. cerevisiae, we demonstrate a preferential requirement of Zuo1p for cap-independent translation mediated by the 5′ untranslated region of the yeast TFIID mRNA. Further studies using zuo1ΔS. cerevisiae complemented with various Zuo1p mutants indicate that the DnaJ domain of Zuo1p, known to influence its interaction with HSP-70, significantly affects cap-independent translation. These results demonstrate for the first time a role for an established chaperone protein in cap-independent translation of a cellular mRNA.