9532
In addition , we also show that cdk7 may phosphorylate the carboxy - terminal domain ( CTD ) of RNA pol II in the absence of promoter opening .
 cdk7, RNA pol II
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 cdk7, RNA pol II