471
A structural model for Vpu is proposed in which the membrane anchor precedes a region comprising two amphipathic alpha - helices of opposed polarity , joined by a strongly acidic turn that protrudes into the cytoplasm and contains the CK - 2 phosphorylation sites .
 GENE: Vpu; GENE: CK - 2 phosphorylation sites
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: Vpu; GENE: CK - 2 phosphorylation sites