7588
We found that RARs were involved in RA -mediated apoptosis of myeloid progenitor cells, whereas RARs as well as RXRs were involved in RA -mediated apoptosis of erythroid progenitor cells .
 ( protein: RARs, None) , ( cell type: erythroid progenitor cells, None) , ( protein: RXRs, None) , ( protein: RARs, 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: RARs, None) , ( cell type: erythroid progenitor cells, None) , ( protein: RXRs, None) , ( protein: RARs, None) 