Quantitative Characteristics of Gene Regulation by Small RNA (original) (raw)
Figure 3
Threshold-Linear Response of a Reporter Target of RNA-OUT
(A) GFP expressions of strain ZZS35 (is10out+) are plotted on the vertical axis against the promoter activity, defined (as in Figure 2) as the GFP expression of strain ZZS31 (is10out−) grown in identical medium. The different symbols correspond to the different levels of RNA-OUT expressed by the PLtet-O1 promoter. The latter was controlled by varying amounts of aTc added to the growth medium (see legend). The solid lines are the steady-state solution (Equation 2) using the best-fit parameters listed in Table S2.
(B) Ratio of GFP expression in is10out+ (ZZS35) and is10out− (ZZS31) strains measured through GFP fluorescence (solid bars) and RT-PCR (striped bars). Expression of RNA-OUT was induced by 10 ng/ml aTc (red), whereas target expression was induced with 0.3 mM IPTG [corresponding to the 4th diamond from the right in (A)]. Change in the mRNA level of cris10-gfp (striped bars) is insignificant compared with changes in GFP fluorescence (solid bars).