The first evidence that RNA can function as a regulator of gene expression came from experiments with prokaryotes in the 1980 s. It was shown that Escherichia coli micF isan independent gene,has its own promoter,and e...The first evidence that RNA can function as a regulator of gene expression came from experiments with prokaryotes in the 1980 s. It was shown that Escherichia coli micF isan independent gene,has its own promoter,and encodes a small non-coding RNA that base pairs with and inhibits translation of a target messenger RNA in response to environmental stress conditions. The mic F RNA was isolated,sequenced and shown to be a primary transcript. In vitro experiments showed binding to the target ompF mR NA. Secondary structure probing revealed an imperfect micF RNA/ompF RNA duplex interaction and the presence of a non-canonical base pair. Several transcription factors,including OmpR,regulate micF transcription in response to environmental factors. micF has also been found in other bacterial species,however,recently Gerhart Wagner and J?rg Vogel showed pleiotropic effects and found micF inhibits expression of multiple target mR NAs; importantly,one is the global regulatory gene lrp. In addition,micF RNA was found to interact with its targets in different ways; it either inhibits ribosome binding or induces degradation of the message. Thus the concept and initial experimental evidence that RNA can regulate gene expression was born with prokaryotes.展开更多
基金support from the Department of Molecular Genetics and Microbiology,Stony Brook University
文摘The first evidence that RNA can function as a regulator of gene expression came from experiments with prokaryotes in the 1980 s. It was shown that Escherichia coli micF isan independent gene,has its own promoter,and encodes a small non-coding RNA that base pairs with and inhibits translation of a target messenger RNA in response to environmental stress conditions. The mic F RNA was isolated,sequenced and shown to be a primary transcript. In vitro experiments showed binding to the target ompF mR NA. Secondary structure probing revealed an imperfect micF RNA/ompF RNA duplex interaction and the presence of a non-canonical base pair. Several transcription factors,including OmpR,regulate micF transcription in response to environmental factors. micF has also been found in other bacterial species,however,recently Gerhart Wagner and J?rg Vogel showed pleiotropic effects and found micF inhibits expression of multiple target mR NAs; importantly,one is the global regulatory gene lrp. In addition,micF RNA was found to interact with its targets in different ways; it either inhibits ribosome binding or induces degradation of the message. Thus the concept and initial experimental evidence that RNA can regulate gene expression was born with prokaryotes.
