Figure 5.

The Mo-MuLV Env interacts with TLR4. (A) Plasmid pHIT123 encoding the Mo-MuLV Env protein was cotransfected with TLR4N and TLR4J, and extracts were prepared and immunoprecipitated with anti-FLAG antibody. Western blots were performed with goat anti-MuLV antisera. (B) One plate of 293T cells was cotransfected with pHIT 123 and the TLR4N expression plasmid; another plate was transfected with the MMTV Env expression plasmid. Extracts were prepared from both transfections, and increasing amounts of the MMTV Env-containing extract was added to the MuLV/TLR4N extract as indicated in rows 1 and 2. As controls, extract from untransfected 293T cells was added in the same increasing increments to the MuLV/TLR4N extract (row 3). The extracts were precipitated with mouse anti-FLAG antiserum, and then Western blots were performed with anti-MuLV antisera (rows 1 and 3). Blot A was stripped and reprobed with anti-MMTV antisera (row 2).