843
GAL4 - VP16 - mediated antirepression required an auxiliary factor , denoted as a co - antirepressor , which was partially purified from Drosophila embryos .
 GAL4, VP16
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 GAL4, VP16