+-------------------SUBJ:V-N------------------+                                  
      +--------------COMP:N-N(of)-------------+     +---------COMP:V-N(in)--------+    
      |           +-------MOD_ATT:N-ADJ-------+     |         +---MOD_ATT:N-ADJ---+    
      |           |       +---MOD_ATT:N-ADJ---+     |         |      +MOD_ATT:N-AD+    
      |           |       |          +MOD_ATT:+     |         |      |     +MOD_AT+    
      |           |       |          |        |     |         |      |     |      |    
 Expression of __SP__ __NODE__ [__NODE___2] mRNA occurs in normal __SP__ liver tissue .
COMP:N-N(of) (expression,mRNA)
MOD_ATT:N-ADJ (mRNA,__SP__)
MOD_ATT:N-ADJ (mRNA,__NODE__)
MOD_ATT:N-N (mRNA,[__NODE___2])
SUBJ:V-N (occur,expression)
COMP:V-N(in) (occur,toilet)
MOD_ATT:N-ADJ (toilet,normal)
MOD_ATT:N-ADJ (toilet,__SP__)
MOD_ATT:N-N (toilet,liver)