Figure 1. The shRNA-mediated silencing of LRP-1 inhibits ERK and triggers the activation of JNK signaling pathways.

(A) Total RNAs were purified from FTC133 control clonal cell line (shCTRL) or clonal cells that stably overexpress shRNAs for LRP-1 (shLRP-1). The transcriptional level of LRP-1 was assessed by RT-PCR. β-actin primers were used as a normalization control. (B) Whole-cell extracts from each cell line were subjected to immunoblot analysis with anti-LRP-1 β-chain antibody (5A6). β-actin antibody was used for normalization. (C) shCTRL and shLRP-1 clonal cells were cultivated for 24 hours on gelatin-coated surfaces in 10% FBS-containing media. Whole-cell extracts were immunoblotted by using phospho-ERK, phospho-JNK, phospho-Akt and phospho-p38 antibodies. Antibodies to ERK, JNK, p38 and β-actin were used to ensure equal loading and for normalization. The gel and immunoblots presented are representative of at least three seperate experiments. Numbers under the gel and immunolots indicate the fold inductions by comparaison with shCTRL cells.