Promoter determinants forEscherichia coliRNA polymerase holoenzyme containing σ³⁸(therpoSgene product)

Abstract

Sequence determinants responsible for promoter recognition by RNA polymerase holoenzyme containing sigma 38, the rpoS gene product, were analyzed. In a previous study [Tanaka et al. (1993) Proc. Natl. Acad. Sci. USA, 90, 3511-3515], Escherichia coli promoters were classified into three groups: promoters recognized only by RNA polymerase holoenzyme containing sigma 70 (E sigma 70); promoters recognized preferentially by that containing sigma 38 (E sigma 38); promoters recognized by both E sigma 70 and E sigma 38. As representatives of each group of promoter, we chose the alaS, fic and lacUV5 promoters. Making use of a restriction enzyme site inserted between the -10 and -35 hexamer sequences, promoters were divided into the upstream (UE) and downstream (DE) elements. These UEs and DEs were combined in all possible combinations and used for in vitro transcription reactions. Promoters containing DE from the fic or lacUV5 promoter were found to be recognized by E sigma 38, while those containing DE from the alaS promoter were not. Moreover, fic DE alone functioned as an efficient promoter for E sigma 38. Thus we conclude that the discrimination signal resides within the DE sequence. To test the activator response of E sigma 38, in vitro transcription reactions were also performed with the gal and lac promoters. For both CRP-responsive P1 promoters, E sigma 38 was found to be activated by the CRP-cAMP complex.

RpoS‐dependent regulation of genes expressed at late stationary phase in Escherichia coli

“…Similarly, the TATACT and TATAAT sequences at the -10 region were reported to be important for promoter recognition by ~ [32]. In the 6 genes reported here (Fig.…”

Regulation of RpoS proteolysis in Escherichia coli : The response regulator RssB is a recognition factor that interacts with the turnover element in RpoS

“…A model for interaction between regions 2.4͞2.5 and promoter sequences downstream of position Ϫ20 was presented recently (44). In the case of RpoS, genetic evidence indicates that interaction with the Ϫ10 region is especially important, such that for some promoters contacts in the Ϫ35 region are dispensible (45). Future studies will have to show whether K173 as the core of region 2.5 in RpoS can directly interact with certain nucleotides in an extended Ϫ10 region of RpoS-controlled promoters.…”

Two Extracytoplasmic Function Sigma Subunits, ς E and ς FecI , of Escherichia coli : Promoter Selectivity and Intracellular Levels

“…Thus, we concluded that the ECF family subunits carry high selectivity for a specific set of the cognate promoters, as in the case of other minor subunits, N , H , and F . In contrast to the strict promoter selectivity characteristic of the minor subunits, the 70 subunit recognizes in vitro most S -dependent promoters, and the S subunit recognizes some 70 -dependent promoters (21,35).…”