Figure 7. The effect of 20E and cycloheximide on the mRNA expression level of the key genes in midgut in vitro culture.

The midguts were cultured with10⁻⁶ M 20E (20E), 10⁻³ M cycloheximide in the hormone-free medium (Chx), in the continuous presence of both 10⁻⁶ M 20E and10⁻³ M Chx (20E+Chx), or with no addition in the medium (control). The mRNA expression levels of four genes, including SeTre-1 (A), SeG6PI (B), SeUAP (C) and SeCHSB (D), were determined using qRT- PCR after incubating for 0 hr, 4 hr, 8 hr and 12 hr. The expression level of each target gene was normalized to the Seβ-actin at each time point, then the mRNA levels in the three treatment groups were normalized to the control group at each time point. The relative expression level of each target gene (y-axis) was calculated as the mRNA level at each time divided by the level at 0 hr in each group. Data are represented as mean ± SE from three independent experiments. Different letters on the broken line (20E incubation group) indicate significant differences among different culture time points in this group. (p<0.05, Duncan multiple comparison test, SPSS).