8123
This system allowed us to efficiently express in developing thymocytes a mutant form of the NF-kappa B inhibitor I kappa B alpha ( mut-I kappa B ) and to study the maturation defects occurring when NF-kappa B activation is inhibited during fetal development.
 ( protein: NF-kappa B, None) , ( protein: NF-kappa B, None) , ( protein: mut-I kappa B, None) , ( protein: I kappa B alpha, 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: NF-kappa B, None) , ( protein: NF-kappa B, None) , ( protein: mut-I kappa B, None) , ( protein: I kappa B alpha, None) 