Affiliation:
1. Department of Molecular Biology and Microbiology, Tufts University School of Medicine, Boston, Massachusetts 02111
Abstract
ABSTRACT
CodY is a global transcriptional regulator known to control expression of more than 100 genes and operons in
Bacillus subtilis
. Some of the most strongly repressed targets of CodY, the
nupNOPQ
(formerly,
yufNOPQ
) genes, were found to encode a guanosine transporter. Using DNase I footprinting experiments, we identified two high-affinity CodY-binding sites in the regulatory region of the
nupN
gene. The two sites are located 50 bp upstream and 163 bp downstream of the transcription start site. The downstream site was responsible for 6- to 8-fold
nupN
repression in the absence of the upstream site. When the upstream site was intact, however, only a minor contribution of the downstream site to
nupN
regulation could be detected under the conditions tested. Both sites contained 15-bp CodY-binding motifs with two mismatches each with respect to the consensus sequence, AATTTTCWGTTTTAA. However, the experimentally determined binding sites included additional sequences flanking the 15-bp CodY-binding motifs. An additional version of the 15-bp CodY-binding motif, with 5 mismatches with respect to the consensus but essential for efficient regulation by CodY, was found within the upstream site. The presence of multiple 15-bp motifs may be a common feature of CodY-binding sites.
Publisher
American Society for Microbiology
Subject
Molecular Biology,Microbiology
Cited by
15 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献