+------------SUBJ:V-N------------+--------COMP:V-N(in)--------+    
      +-------COMP:N-N(of)-------+     |          +--MOD_ATT:N-ADJ--+    
      |           +-MOD_ATT:N-ADJ+     |          |      +MOD_ATT:N-+    
      |           |       +MOD_AT+     |          |      |     +MOD_+    
      |           |       |      |     |          |      |     |    |    
 Expression of __SP__ __NODE__ mRNA occurs in salivary gland cell lines .
COMP:N-N(of) (expression,mRNA)
MOD_ATT:N-ADJ (mRNA,__SP__)
MOD_ATT:N-ADJ (mRNA,__NODE__)
SUBJ:V-N (occur,expression)
COMP:V-N(in) (occur,line)
MOD_ATT:N-ADJ (line,salivary)
MOD_ATT:N-N (line,gland)
MOD_ATT:N-N (line,cell)