Pieler T, Erdmann V A, Appel B
Nucleic Acids Res. 1984 Nov 26;12(22):8393-406. doi: 10.1093/nar/12.22.8393.
In order to study the binding of the eukaryotic transcription factor IIIA to heterologous 5S rRNAs with a low degree of overall sequence conservation (less than 20%) we have utilized a transcription competition assay involving eubacterial, archaebacterial and eukaryotic 5S rRNAs. All the molecules inhibit Xenopus 5S rRNA transcription specifically, which suggests that only a small amount of specific conserved RNA sequences, if indeed any, are essential for the interaction of the transcription factor with the 5S rRNA molecule, whereas universal 5S rRNA secondary structure elements seem to be required. A fragment of Xenopus laevis oocyte 5S rRNA (nucleotides 41-120), which partially maintains the original 5S rRNA structure, also competes for TF III A. In vitro transcription of a naturally occurring mutant of the Xenopus laevis oocyte 5S rRNA gene, the pseudogene, which carries several point mutations within the TF III A binding domain is equally inhibited by exogenous Xenopus 5S rRNA.
为了研究真核转录因子IIIA与总体序列保守程度较低（低于20%）的异源5S rRNA的结合情况，我们采用了一种转录竞争分析方法，该方法涉及真细菌、古细菌和真核生物的5S rRNA。所有这些分子都能特异性抑制非洲爪蟾5S rRNA的转录，这表明对于转录因子与5S rRNA分子的相互作用而言，即便确实存在，也只有少量特定的保守RNA序列是必不可少的，而5S rRNA的通用二级结构元件似乎是必需的。非洲爪蟾卵母细胞5S rRNA的一个片段（核苷酸41 - 120），它部分保留了原始5S rRNA的结构，也能与TF III A竞争。非洲爪蟾卵母细胞5S rRNA基因的一个天然存在的突变体——假基因，其在TF III A结合域内有几个点突变，该假基因的体外转录同样受到外源非洲爪蟾5S rRNA的抑制。
