3998
The two SH3 domains are separated by a 54 amino acid linker region , whose length is highly conserved in xenopus , chicken , and mamalian Crk II proteins .
 GENE: SH3 domains; GENE: mamalian Crk II proteins
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: SH3 domains; GENE: mamalian Crk II proteins