4253
Active suppression of the class II transactivator-encoding AIR-1 locus is responsible for the lack of major histocompatibility complex class II gene expression observed during differentiation from B cells to plasma cells .
 ( DNA: class II transactivator-encoding AIR-1 locus, None) , ( DNA: major histocompatibility complex class II gene, None) , ( cell type: plasma cells, None) , ( cell type: B cells, 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:
 ( DNA: class II transactivator-encoding AIR-1 locus, None) , ( DNA: major histocompatibility complex class II gene, None) , ( cell type: plasma cells, None) , ( cell type: B cells, None) 