Abstract：
In recent years, numerous evidence has been accumulated about the extent of A-to-I editing in human RNAs and the key role ADAR1 plays in the cellular editing machinery. It has been shown that A-to-I editing occurrence and frequency are tissue-specific and essential for some tissue development, such as the liver. To study the effect of ADAR1 function in hepatocytes, we have created Huh7.5 ADAR1 KO cell lines. Upon IFN treatment, the Huh7.5 ADAR1 KO cells show rapid arrest of growth and translation, from which they do not recover. We analyzed translatome changes by using a method based on sequencing of separate polysome profile RNA fractions. We found significant changes in the transcriptome and translatome of the Huh7.5 ADAR1 KO cells. The most prominent changes include negatively affected transcription by RNA polymerase III and the deregulation of snoRNA and Y RNA levels. Furthermore, we observed that ADAR1 KO polysomes are enriched in mRNAs coding for proteins pivotal in a wide range of biological processes such as RNA localization and RNA processing, whereas the unbound fraction is enriched mainly in mRNAs coding for ribosomal proteins and translational factors. This indicates that ADAR1 plays a more relevant role in small RNA metabolism and ribosome biogenesis.
摘要：
近年来,关于人类RNA中A-I编辑的程度以及ADAR1在细胞编辑机制中的关键作用，已经积累了许多证据。已经表明，A-to-I编辑的发生和频率是组织特异性的，并且对于某些组织发育是必不可少的，比如肝脏。研究ADAR1对肝细胞功能的影响,我们已经创建了Huh7.5ADAR1KO细胞系。IFN治疗后，Huh7.5ADAR1KO细胞显示生长和翻译的快速停滞，他们无法从中恢复过来。我们通过采用基于对单独的多体谱RNA部分进行测序的方法分析了翻译体的变化。我们发现Huh7.5ADAR1KO细胞的转录组和翻译组发生显著变化。最突出的变化包括RNA聚合酶III对转录的负面影响以及snoRNA和YRNA水平的失调。此外，我们观察到ADAR1KO多聚体富含编码蛋白质的mRNA，这些蛋白质在广泛的生物过程中至关重要，例如RNA定位和RNA加工，而未结合的部分主要富集在编码核糖体蛋白和翻译因子的mRNA中。这表明ADAR1在小RNA代谢和核糖体生物发生中起着更重要的作用。
