+-MOD_PRED:N-ADJ-+              +----COMP:N-N(of)---+          
     +MOD_ATT:N+         +MOD:AD+COMP:ADJ-N(for+           +MOD_ATT+          
     |         |         |      |              |           |       |          
 __NODE__ protein(s) is not necessary for activation of __SP__ __NODE__ gene .
MOD_ATT:N-ADJ (protein(s),__NODE__)
MOD_PRED:N-ADJ (protein(s),necessary)
MOD:ADJ-ADV (necessary,not)
COMP:ADJ-N(for) (necessary,activation)
COMP:N-N(of) (activation,__NODE__)
MOD_ATT:N-ADJ (__NODE__,__SP__)