UMR5240 Microbiologie Adaptation et Pathogénie, CNRS, Université de Lyon, Lyon, France.
Biochimie. 2011 Mar;93(3):434-9. doi: 10.1016/j.biochi.2010.10.016. Epub 2010 Oct 30.
RcnA is an efflux pump responsible for Ni and Co detoxification in Escherichia coli. The expression of rcnA is induced by Ni and Co via the metallo-regulator RcnR. In the present work, the functioning of the promoter-operator region of rcnR and rcnA was investigated using primer extension and DNAse I footprinting experiments. We show that the promoters of rcnR and rcnA are convergent and that apo-RcnR binds on symmetrically located sequences in this intergenic region. Moreover, RcnR DNA binding is specifically modulated by one Ni or Co equivalent and not by other metals. In addition to rcnA, RcnR controls expression of its own gene in response to Ni and Co, but the two genes are differentially expressed.
RcnA 是一种外排泵，负责大肠杆菌中 Ni 和 Co 的解毒。rcnA 的表达受 Ni 和 Co 通过金属调节剂 RcnR 诱导。在本工作中，使用引物延伸和 DNAse I 足迹实验研究了 rcnR 和 rcnA 启动子-操纵子区域的功能。我们表明，rcnR 和 rcnA 的启动子是会聚的，并且 apo-RcnR 结合在这个基因间区域中对称定位的序列上。此外，RcnR 的 DNA 结合受一个 Ni 或 Co 当量特异性调节，而不受其他金属调节。除了 rcnA，RcnR 还响应 Ni 和 Co 控制自身基因的表达，但这两个基因的表达水平不同。
