Transcriptional analysis of the lysine-responsive and riboswitch-regulated lysC gene of Bacillus subtilis.
About 2% of the Bacillus subtilis genes are subject to regulation by riboswitch-controlled mechanisms. One of them is the L-lysine-dependent lysC gene which is turned on when the L-lysine concentration within the cytoplasm is low. In the presence of a high L-lysine concentration, only a 0.27-kb transcript is synthesized representing the riboswitch due to transcription termination. When the L-lysine concentration is low, the full-length 1.6-kb transcript is produced due to transcription anti-termination. Here, we show for the first time that even under conditions of transcription anti-termination the truncated form of the RNA is still predominant. This 0.27-kb transcript is neither the result of enhanced stability nor does it result from processing of the full-length transcript. When the region coding for the transcription terminator was removed, the riboswitch RNA failed to be produced. These data were confirmed by analysis of a transcriptional fusion between the promoter-riboswitch region of lysC with and without a functional transcriptional terminator and the lacZ reporter gene. The putative function(s) of the riboswitch under conditions of low L-lysine concentration is discussed.
Phan
Trang Thi Phuong
TT
Institute of Genetics, University of Bayreuth, Bayreuth, Germany.
Schumann
Wolfgang
W
D019677:Artificial Gene Fusion; D001412:Bacillus subtilis / Q000502:physiology*; D020869:Gene Expression Profiling; D015964:Gene Expression Regulation, Bacterial; D017930:Genes, Reporter; D008239:Lysine / Q000378:metabolism*; D012329:RNA, Bacterial / Q000096:biosynthesis; D012333:RNA, Messenger / Q000096:biosynthesis; D001616:beta-Galactosidase / Q000235:genetics / Q000378:metabolism
D012329:RNA, Bacterial; D012333:RNA, Messenger; D001616:beta-Galactosidase; D008239:Lysine