Open AccessExpression of micF involved in porin synthesis in Escherichia coli : two distinct cis ‐acting elements respectively regulate micF expression positively and negatively
Author(s) -
Takayanagi Katsuhiko,
Maeda Sumio,
Mizuno Takeshi
Publication year - 1991
Publication title -
fems microbiology letters
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.899
H-Index - 151
eISSN - 1574-6968
pISSN - 0378-1097
DOI - 10.1111/j.1574-6968.1991.tb04385.x
Subject(s) - porin , gene , escherichia coli , biology , function (biology) , gene expression , regulator gene , regulation of gene expression , genetics , microbiology and biotechnology , bacterial outer membrane
micF RNA, whose sequence is highly complementary to a 5′‐portion of ompF mRNA, has been implicated in the osmoregulation and thermoregulation of the ompF porin gene in Escherichia coli . To define and characterize cis ‐acting regulatory regions upstream of the micF promoter, a series of deletions of the micF promoter fused to the lacZ gene were constructed. Two distinct regions, which function differently, were identified as cis ‐acting regulatory elements, namely, one responsible for OmpR‐dependent activation and the other for OmpR‐independent repression of micF expression. The former contains the OmpR‐binding site, which simultaneously regulates both the genes, micF and ompC , in response to the medium osmolarity. The latter may be involved in an unknown regulatory process of micF expression.