Khalili K, Weinmann R
J Mol Biol. 1984 Jun 5;175(4):453-68. doi: 10.1016/0022-2836(84)90179-7.
Adenovirus produces a dramatic shut-off of host protein synthesis after infection of HeLa cells. The level of actin messenger RNAs remained relatively unchanged after viral infection, when assayed by in vitro translation and two-dimensional gel electrophoresis analysis of the proteins or hybridization of the total cytoplasmic RNAs to the human actin gene. The distribution of actin mRNA in the polyribosomes is altered after adenovirus infection, with small polyribosomes and monoribosomes of the infected cells occupied by actin messages untranslatable in a rabbit reticulocyte lysate. The large polyribosomes still retain enough functional mRNAs to provide significant levels of actin protein in a rabbit reticulocyte in vitro translation system. In contrast, in homologous infected cell lysates, the translation of exogenous actin mRNA is greatly reduced when compared to uninfected HeLa cell lysates. In nuclease-treated uninfected or infected HeLa cell-free extracts, translation of viral mRNA is equally efficient and higher than that of actin mRNA. Thus, translational regulatory mechanisms which include inactivation of a part of the actin mRNA population accompanied by displacement to small polysomes and/or virus-induced modification of the cellular translational machinery to discriminate against cellular actin mRNA seem to account for the sharp reduction in actin protein synthesis of adenovirus-infected cells.
腺病毒感染HeLa细胞后会导致宿主蛋白质合成急剧停止。通过体外翻译、蛋白质二维凝胶电泳分析或总细胞质RNA与人肌动蛋白基因杂交检测发现，病毒感染后肌动蛋白信使RNA水平相对保持不变。腺病毒感染后，肌动蛋白mRNA在多核糖体中的分布发生改变，感染细胞的小多核糖体和单核糖体被肌动蛋白信息占据，这些信息在兔网织红细胞裂解物中无法翻译。大的多核糖体仍保留足够的功能性mRNA，以在兔网织红细胞体外翻译系统中提供显著水平的肌动蛋白。相反，与未感染的HeLa细胞裂解物相比，在同源感染细胞裂解物中，外源肌动蛋白mRNA的翻译大大减少。在经核酸酶处理的未感染或感染的HeLa无细胞提取物中，病毒mRNA的翻译效率相同且高于肌动蛋白mRNA。因此，翻译调控机制，包括部分肌动蛋白mRNA群体失活并转移到小多核糖体上，和/或病毒诱导的细胞翻译机制修饰以区分细胞肌动蛋白mRNA，似乎是腺病毒感染细胞中肌动蛋白合成急剧减少的原因。
