+------------COMP:N-N(of)-----------+      
                       |          +-------MOD_ATT:N-N------+      
                       |          |       +--MOD_ATT:N-ADJ-+      
     +SUBJ:V-+-OBJ:V-N-+          |       |       +MOD_ATT:+      
     |       |         |          |       |       |        |      
 __NODE__ affects expression of serum __NODE__ levels [__NODE__] .
SUBJ:V-N (affect,__NODE__)
OBJ:V-N (affect,expression)
COMP:N-N(of) (expression,[__NODE__])
MOD_ATT:N-N ([__NODE__],serum)
MOD_ATT:N-ADJ ([__NODE__],__NODE__)
MOD_ATT:N-N ([__NODE__],level)