L-box
The L-box is a riboswitch that binds lysine and controls gene expression by a termination/ antitermination mechanism. Upon binding of lysine, the L-box adopts a terminator structure thtus preventing expression of lysC. In the absence of lysine, the L-box has an antiterminator structure that allows lysC expression and thus lysine biosynthesis.
Gene controlled by a L-box mechanism
References
<pubmed> 14523230, 17143270 ,14597663 14627808 21169337 22416067 23067368 14627808 </pubmed>