4013
From these results, we can conclude that electrostatic interactions of retinoids with the RAR alpha -LBD play a significant role in ligand binding .
 ( protein: RAR alpha, None) , ( protein: RAR alpha -LBD, 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: RAR alpha, None) , ( protein: RAR alpha -LBD, None) 