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; protein: retinoic acid receptors; protein: retinoid X receptors
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: cell line, protein, RNA, DNA, cell type 
Text: {0} 
 Entities: RXRs, retinoic acid receptors, retinoid X receptors 
Answer:
 protein: RXRs; protein: retinoic acid receptors; protein: retinoid X receptors