Isolation and characterization of the 102-kilodalton RNA-binding protein that binds to the 5' and 3' translational enhancers of tobacco mosaic virus RNA
Isolation and characterization of the 102-kilodalton RNA-binding protein that binds to the 5' and 3' translational enhancers of tobacco mosaic virus RNA
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DOI：
10.1074/jbc.271.24.14316
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发表时间：
1996-06-14
影响因子：
4.8
通讯作者：
Gallie, DR
中科院分区：
文献类型：
--
作者：
Tanguay, RL;Gallie, DR
烟草花叶病毒（TMV）是一种正义、单链RNA病毒，其基因组在细胞质中充当mRNA，在感染时，尽管缺乏poly（A）尾，但TMV mRNA仍被宿主翻译机制有效且选择性地翻译，而poly（A）尾通常是高效翻译所需的，TMV的68个碱基的5'前导区（Omega）和205个碱基的3'非翻译区都促进有效翻译，Omega内的25个碱基的多聚（CAA）区和上游假结结构域，由三个RNA假结组成的72个碱基的区域，我们已经鉴定、纯化和表征了来自小麦的102-kDa RNA结合蛋白（p102），其特异性结合Omega内的poly（CAA）区域和TMV 3'非翻译区内的上游假结结构域，针对小麦p102的多克隆抗体被用来证明p102在植物物种中广泛保守。此外，在所有测试的植物物种中检测到特异性RNA结合活性。将抗p102抗体添加到来自小麦胚芽的体外翻译裂解物中抑制翻译，随后通过用p102补充裂解物来逆转翻译。这些发现表明，这种蛋白质可能在决定植物中的翻译效率中起重要作用。
Tobacco mosaic virus (TMV) is a positive-sense, single-stranded RNA virus the genome of which acts as a mRNA in the cytoplasm, On infection, TMV mRNA is efficiently and selectively translated by the host translation machinery despite the lack of a poly(A) tail, which is normally required for efficient translation, Both the 68-base 5' leader (Omega) and the 205-base 3' untranslated region of TMV promote efficient translation, A 25-base poly(CAA) region within Omega and the upstream pseudoknot domain, a 72-base region composed of three RNA pseudoknots, are responsible for the translational regulation, We have identified, purified, and characterized a 102-kDa RNA-binding protein (p102) from wheat that binds specifically to the poly(CAA) region within Omega and the upstream pseudoknot domain within the TMV 3' untranslated region, Polyclonal antibodies raised against wheat p102 were used to demonstrate that p102 is widely conserved in plant species. Moreover, specific RNA binding activity was detected in all plant species tested. Addition of anti-p102 antibodies to an in vitro translation lysate derived from wheat germ repressed translation, which was subsequently reversed by supplementing the lysate with p102, These findings suggest that this protein may play an important role in determining translational efficiency in plants.