1750
The sequence between position -42 and -76 base pairs (bp) was required for efficient transcription in cells that express alpha 4 , but it showed no activity in HeLa cells , which do not express alpha 4 .
 ( cell line: HeLa cells, None) , ( DNA: -42 and -76 base pairs, None) , ( protein: alpha 4, None) , ( protein: alpha 4, 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:
 ( cell line: HeLa cells, None) , ( DNA: -42 and -76 base pairs, None) , ( protein: alpha 4, None) , ( protein: alpha 4, None) 