4068
Finally, both PU.1 and Spi-B function as transcriptional activators of the immunoglobulin light-chain enhancer E lambda 2.4 when coexpressed with Pip ( PU.1 -interaction partner ) in NIH-3T3 cells .
 ( protein: PU.1, None) , ( protein: PU.1 -interaction partner, None) , ( cell line: NIH-3T3 cells, None) , ( DNA: immunoglobulin light-chain enhancer, None) , ( DNA: immunoglobulin light-chain enhancer E lambda 2.4, None) , ( DNA: E lambda 2.4, None) , ( protein: Spi-B, None) , ( protein: PU.1, None) , ( protein: Pip, 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: PU.1, None) , ( protein: PU.1 -interaction partner, None) , ( cell line: NIH-3T3 cells, None) , ( DNA: immunoglobulin light-chain enhancer, None) , ( DNA: immunoglobulin light-chain enhancer E lambda 2.4, None) , ( DNA: E lambda 2.4, None) , ( protein: Spi-B, None) , ( protein: PU.1, None) , ( protein: Pip, None) 