+--------------SUBJ:V-N-------------+                           
      +--------COMP:N-N(of)-------+       +-----COMP:V-N(in)-----+    
      |           +-MOD_ATT:N-ADJ-+       |         +MOD_ATT:N-AD+    
      |           |       +MOD_ATT+       |         |      +MOD_A+    
      |           |       |       |       |         |      |     |    
 Expression of __SP__ __NODE__ protein occurs in smooth muscle cells .
COMP:N-N(of) (expression,protein)
MOD_ATT:N-ADJ (protein,__SP__)
MOD_ATT:N-ADJ (protein,__NODE__)
SUBJ:V-N (occur,expression)
COMP:V-N(in) (occur,cell)
MOD_ATT:N-ADJ (cell,smooth)
MOD_ATT:N-N (cell,muscle)