7587
To explore the receptor signaling pathways involved in RA -induced apoptosis , we used selective ligands for retinoic acid receptors ( RARs ; RO13-7410) and retinoid X receptors ( RXRs ; RO 25-6603).
 ( protein: RXRs, None) , ( protein: retinoic acid receptors, None) , ( protein: retinoid X receptors, None) 
Locate the role in the text that participated in the event based on the event type and return it in the event list. 
 Option: Event type: RNA,cell type,protein,cell line,DNA, Arguments type: . 
Text: {0} 
Answer:
 ( protein: RXRs, None) , ( protein: retinoic acid receptors, None) , ( protein: retinoid X receptors, None) 