+------------------SUBJ:V-N-----------------+                    
      +--------COMP:N-N(of)-------+               |                    
      |           +-MOD_ATT:N-ADJ-+               +--COMP:V-N(in)-+    
      |           |       +MOD_ATT+          +-NEG+         +MOD_A+    
      |           |       |       |          |    |         |     |    
 Expression of __SP__ __NODE__ protein does not occur in __SP__ serum .
COMP:N-N(of) (expression,protein)
MOD_ATT:N-ADJ (protein,__SP__)
MOD_ATT:N-ADJ (protein,__NODE__)
SUBJ:V-N (occur,expression)
NEG (occur,not)
COMP:V-N(in) (occur,serum)
MOD_ATT:N-ADJ (serum,__SP__)