Protein expression from the lac -operon after treatment with antisense PNA directed to lacZ and lacY mRNA start codon regions. (A) Structure of the lac-operon with antisense target sites on the mRNA indicated by small arrows. The solid bars below indicate amplified regions in subsequent qPCR experiments. Relative amounts of LacZ (triangles), LacY (squares) and LacA protein (diamonds) were detected in cultures induced with 100 μM IPTG and treated with increasing concentrations of either anti-lacZ (B) or anti-lacY PNA (C). Data points show the mean from triplicate samples where non-treated samples are used as standard and un-induced samples are used to remove noise from the assays.