7674
Signaling through HLA class I molecules induced cyclin E -associated kinase activity within 4 h in quiescent endothelial cells , and appeared to mediate the inactivation of Rb .
 ( cell type: quiescent endothelial cells, None) , ( protein: HLA class I molecules, None) , ( DNA: cyclin E, None) , ( protein: Rb, 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 type: quiescent endothelial cells, None) , ( protein: HLA class I molecules, None) , ( DNA: cyclin E, None) , ( protein: Rb, None) 