FIG 5.

Effect of Y-complex mutations on the cellular levels of yitJ SAM riboswitch RNA and the thrS leader mRNA. Northern blot analysis of the prematurely terminated yitJ and thrS 5′ riboswitch RNAs (201 nt and 280 nt, respectively). Total RNA isolated from the indicated strains grown to mid-exponential phase in LB medium was separated on a denaturing 8% acrylamide gel and hybridized to specific continuously labeled RNA probes as described in Materials and Methods. The following strains were analyzed: SSB1002 (WT), SSB576 (ΔyaaT), SSB577 (ΔymcA), SSB578 (ΔylbF), SSB579 (ΔyaaT ΔylbF), SSB580 (ΔyaaT ΔymcA), SSB581 (ΔymcA ΔylbF), SSB582 (ΔyaaT ΔymcA ΔylbF), and SSB503 (Δrny). Hybridization to 5S RNA was used as a loading control.