x1 = cyclin
x2 = dimer
x3 = dimer_p
x4 = p_dimer
x5 = p_dimer_p
x6 = cdc25_p
x7 = wee1_p
x8 = IE_p
x9 = UbE_star
x10 = cdc2
x11 = cdc25
x12 = wee1
x13 = IE
x14 = UbE