x1 = Raf1
x2 = RKIP
x3 = Raf1_RKIP
x4 = Raf1_RKIP_ERKPP
x5 = ERK
x6 = RKIPP
x7 = MEKPP
x8 = MEKPP_ERK
x9 = ERKPP
x10 = RP
x11 = RKIPP_RP