Skip to main content
. 2009 Apr 21;7:8. doi: 10.1186/1478-811X-7-8

Figure 2.

Figure 2

Design and biological activity of a conditionally active forms of Raf. (A) Strategy: A heterologous protein is expressed as a fusion protein with the ligand-binding domain of the estrogen receptor. The fusion protein, that is constitutively expressed, remains in an inactive state, due to the binding of chaperons of the Hsp90 family. The repression is reversed by adding hormone. (B) Modular structure of Raf and ΔRaf:ER, a conditionally active form of Raf-1. (C) Biologically active ΔRaf-1:ER triggers phosphorylation and activation of ERK2. HT22 cells, murine cells of hippocampal origin, and HT22-ΔRaf-1:ER cells were treated with 4OHT (+) or left untreated (-). Whole cell extracts were prepared 15 min after stimulation and subjected to Western blot analysis. The blots were incubated with a rabbit antibody directed against the phosphorylated form of ERK1/2.