Figure 4

Northern blot analysis of five novel sRNAs in prophages. Total RNA was isolated from E. coli cells grown to exponential (E) or stationary (S) phase in LB medium or M63 minimal medium and from cells subjected to heat shock (HS) or cold shock (CS). Total RNA was also isolated from the hfq knockout strain grown to exponential phase in M63 minimal medium (Δhfq). 5S rRNA expression is shown as the loading control.