+------------------SUBJ:V-N-----------------+                    
      +--------COMP:N-N(of)-------+               +--COMP:V-N(in)-+    
      |           +-MOD_ATT:N-ADJ-+               |       +MOD_ATT+    
      |           |       +MOD_ATT+          +-NEG+       |   +MOD+    
      |           |       |       |          |    |       |   |   |    
 Expression of __SP__ __NODE__ mRNA(s) does not occur in 3T3 L1 cells .
COMP:N-N(of) (expression,mRNA(s))
MOD_ATT:N-ADJ (mRNA(s),__SP__)
MOD_ATT:N-ADJ (mRNA(s),__NODE__)
SUBJ:V-N (occur,expression)
NEG (occur,not)
COMP:V-N(in) (occur,cell)
MOD_ATT:N-ADJ (cell,3T3)
MOD_ATT:N-N (cell,L1)