Bogenhagen D F, Sands M S
Department of Pharmacological Sciences, SUNY, Stony Brook 11794-8651.
Nucleic Acids Res. 1992 Jun 11;20(11):2639-45. doi: 10.1093/nar/20.11.2639.
The repetitive zinc finger domain of transcription factor IIIA binds 5S DNA and 5S RNA with similar affinity. Site directed mutagenesis of the Xenopus borealis somatic 5S RNA gene has been used to produce a series of derivatives of 5S RNA containing local sequence substitutions or sequence deletions. Gel mobility shift analyses of the binding of TFIIIA to these altered 5S RNAs revealed that all three of the helical stems of the 5S RNA secondary structure are required for binding. TFIIIA was observed to bind with normal affinity to RNAs lacking 12 nucleotides at either the loop c or loop e/helix V regions of 5S RNA, as well as to a double mutant containing both deletions. The secondary structure of the resulting 96-nucleotide RNA, studied using structure-specific ribonucleases, was found to resemble the central portion of 5S RNA.
转录因子IIIA的重复锌指结构域以相似的亲和力结合5S DNA和5S RNA。利用非洲爪蟾体细胞5S RNA基因的定点诱变技术，产生了一系列含有局部序列替换或序列缺失的5S RNA衍生物。对TFIIIA与这些改变后的5S RNA结合的凝胶迁移率变动分析表明，5S RNA二级结构的所有三个螺旋茎对于结合都是必需的。观察到TFIIIA以正常亲和力结合缺乏5S RNA环c或环e/螺旋V区域12个核苷酸的RNA，以及同时含有这两个缺失的双突变体。使用结构特异性核糖核酸酶研究所得96个核苷酸RNA的二级结构，发现其类似于5S RNA的中央部分。
