An mRNA structure in bacteria that controls gene expression by binding lysine.
Riboswitches are metabolite-responsive genetic control elements that reside in the untranslated regions (UTRs) of certain messenger RNAs. Herein, we report that the 5'-UTR of the lysC gene of Bacillus subtilis carries a conserved RNA element that serves as a lysine-responsive riboswitch. The ligand-binding domain of the riboswitch binds to L-lysine with an apparent dissociation constant (KD) of approximately 1 micro M, and exhibits a high level of molecular discrimination against closely related analogs, including D-lysine and ornithine. Furthermore, we provide evidence that this widespread class of riboswitches serves as a target for the antimetabolite S-(2-aminoethyl)-L-cysteine (AEC). These findings add support to the hypotheses that direct sensing of metabolites by messenger RNAs is a fundamental form of genetic control and that riboswitches represent a new class of antimicrobial drug targets.
Sudarsan
Narasimhan
N
Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut 06520-8103, USA.
Wickiser
J Kenneth
JK
Nakamura
Shingo
S
Ebert
Margaret S
MS
Breaker
Ronald R
RR
D020121:5' Untranslated Regions; D001222:Aspartate Kinase / Q000235:genetics*; D001412:Bacillus subtilis / Q000201:enzymology / Q000235:genetics; D001665:Binding Sites; D004926:Escherichia coli / Q000201:enzymology / Q000235:genetics; D015964:Gene Expression Regulation, Bacterial / Q000502:physiology*; D008239:Lysine / Q000378:metabolism*; D012333:RNA, Messenger / Q000378:metabolism*
D020121:5' Untranslated Regions; D012333:RNA, Messenger; C116188:lysC aspartokinase; D001222:Aspartate Kinase; D008239:Lysine