+---COMP:N-N(of)--+      
    +SUBJ:V-N+--OBJ:V-N-+         +MOD_ATT+      
    |        |          |         |       |      
 Hypoxia increases activation of Pfk protein(s) .
SUBJ:V-N (increase,hypoxia)
OBJ:V-N (increase,activation)
COMP:N-N(of) (activation,protein(s))
MOD_ATT:N-N (protein(s),Pfk)