Figure 1
MAP3K4 immunoprecipitations from MCF-7 breast cancer cells stimulated by HRG or sorbitol. A schematic representation of MAP3K4 domains identifying antibody epitopes directed against MAP3K4. The MAP3K4 (P) antibody recognizes an amino terminal region (amino acids 18–139) of MAP3K4 that is proline rich, while the MAP3K4 (A) antibody recognizes an internal region (amino acids 1,102–1,255) of MAP3K4 that is alanine rich (Panel A). Cells were stimulated with 10 nM HRG for 10 minutes or 0.3 M sorbitol for 30 minutes. Lysates were incubated with anti MAP3K4 (A) or anti MAP3K4 (P) antibody and precipitated with Protein A–Sepharose. Immunoprecipitated proteins were separated by SDS-PAGE. Proteins were transferred to nitrocellulose membrane and immunoblotted using the indicated antibodies (Panel B). MCF-7 cells were treated with 10 nM of HRG for the indicated time in minutes. Proteins were immunoprecipitated for MAP3K4 or MAP3K3, resolved by SDS-PAGE and immunoblotted as indicated (Panel C). Different areas of the nitrocellulose membrane are separated by white space. A vertical line separates groups belonging to different membranes.
