2254
These results are the first to demonstrate the structural organization of a vertebrate gene encoding an integral membrane protein of the nuclear envelope that may be a member of a family of polypeptides conserved in evolution .
 ( protein: integral membrane protein, None) , ( protein: membrane protein, None) , ( DNA: vertebrate gene, 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: integral membrane protein, None) , ( protein: membrane protein, None) , ( DNA: vertebrate gene, None) 