Sklyarova S A, Mironov A S
Genetika. 2014 Mar;50(3):364-8.
We studied the regulation of the Bacillus subtilis ypaA gene-encoding riboflavin-transporter protein involving FMN-dependent sensor RNA. Using translational fusions of the wild-type ypaA gene with the lacZ-reporter gene in the leader region we showed that in vivo ypaA gene expression decreased more than 10-fold in the presence of endogenous FMN. Introduction of two nucleotide substitutions providing stabilization of the sequester hairpins results in almost complete repression of reporter gene expression. Using toeprint assay in vitro it has been shown that FMN presence inhibits the formation of the 30S initiation complexint the ypaA gene leader mRNA. Our results support the model of ypaA gene regulation whereby FMN binding with the ypaA gene leader sequence results in translation suppression through the sequestering of the SD-sequence.
我们研究了枯草芽孢杆菌中编码核黄素转运蛋白的ypaA基因的调控，该调控涉及黄素单核苷酸（FMN）依赖性传感RNA。通过在引导区将野生型ypaA基因与lacZ报告基因进行翻译融合，我们发现，在内源性FMN存在的情况下，体内ypaA基因表达下降了10倍以上。引入两个核苷酸取代以稳定隔离发夹结构，几乎完全抑制了报告基因的表达。体外足迹分析表明，FMN的存在会抑制ypaA基因引导mRNA中30S起始复合物的形成。我们的结果支持ypaA基因调控模型，即FMN与ypaA基因引导序列结合，通过隔离SD序列导致翻译抑制。
