+MOD_ATT:N+SUBJ:V_PASS-+COMP:V_PASS-+COMP:N-N(of+    
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 __NODE__ protein(s) is involved in interaction of cells .
MOD_ATT:N-ADJ (protein(s),__NODE__)
SUBJ:V_PASS-N (involve,protein(s))
COMP:V_PASS-N(in) (involve,interaction)
COMP:N-N(of) (interaction,cell)