MAPK ERK Signaling Regulates the TGF-β1-Dependent Mosquito Response to Plasmodium falciparum
Figure 3
U0126 inhibition of ERK phosphorylation increased TGF-β1-induced NOS expression in Anopheles cells.
(A) U0126 inhibited basal ERK phosphorylation and TGF-β1-induced ERK phosphorylation. ASE cells were pre-treated with 10 µM U0126 for 40 min then treated with 6 or 6000 pg/ml TGF-β1 or an equivalent volume of PBS. ERK phosphorylation (pERK) was examined by western blotting at 5 min after treatment; total ERK levels provided an assessment of protein loading. The immunoblot is representative of 3 independent experiments. (B) U0126 enhanced hTGF-β1-induced AsNOS expression. ASE cells were pre-treated with 10 µM U0126 then treated with 6 pg/ml TGF-β1 for 6, 24 and 48 h. DMSO and U0126 alone had no impact on AsNOS expression compared to the PBS control (not shown). AsNOS expression was analyzed by quantitative reverse transcriptase-polymerase chain reaction (qRT-PCR) assay. The data are represented as means±standard errors from three independent experiments for fold inductions compared with the PBS control. The data were analyzed by ANOVA for overall significance and Student's t-test was used for the pairwise comparison at 48 h.