468
Our studies indicate no single trans - acting factor is absolutely essential for enhancer activity , and that the enhancer activity of MerI is mediated via a combinatorial and additive mechanism .
 GENE: MerI
Please list all entity words in the text that fit the category.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
Answer:
 GENE: MerI