7987
This mechanism is in contrast to other cases of splicing regulation by PTB , in which the protein represses the splice site to which it binds .
 GENE: PTB
Given options, please tell me the categories of all the listed entity words.Output format is "type1: word1; type2: word2". 
Option: GENE 
Text: {0} 
 Entities: PTB 
Answer:
 GENE: PTB