2175
To test this hypothesis, light-chain gene structure was examined in pre-B cells transformed by temperature-sensitive mutants of the Abelson virus and in derivatives that survive at the nonpermissive temperature because they express a human BCL-2 gene .
 ( cell line: pre-B cells, None) , ( DNA: human BCL-2 gene, None) , ( DNA: light-chain gene structure, 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: pre-B cells, None) , ( DNA: human BCL-2 gene, None) , ( DNA: light-chain gene structure, None) 