8843
These widely expressed proteins share a C - terminal region that bears significant sequence homology to a group of GDP / GTP exchange proteins for the Rab3 family of small GTP binding proteins .
 GDP / GTP exchange proteins, Rab3 family, small GTP binding proteins
Please list all entity words in the text that fit the category. Output format is "word1, word2". 
Option: GENE 
Text: {0} 
Answer:
 GDP / GTP exchange proteins, Rab3 family, small GTP binding proteins