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Heterotrimeric guanine nucleotide - binding proteins ( G - proteins ) function as signal transducers for a variety of hormone - coupled enzyme and ion transport systems in eukaryotic cells .
 GENE: guanine nucleotide - binding proteins; GENE: G - 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: guanine nucleotide - binding proteins; GENE: G - proteins