6657
Here we present genetic evidence suggesting that PP2A functions downstream of Ras1 in the Sevenless receptor tyrosine kinase ( RTK ) signal transduction pathway that specifies R7 photoreceptor cell fate in the developing Drosophila eye .
 GENE: PP2A; GENE: Ras1; GENE: Sevenless; GENE: receptor tyrosine kinase; GENE: RTK
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: PP2A, Ras1, Sevenless, receptor tyrosine kinase, RTK 
Answer:
 GENE: PP2A; GENE: Ras1; GENE: Sevenless; GENE: receptor tyrosine kinase; GENE: RTK