In this task, you are given a sentence. You are expected to recognize the name of gene or protein. Although there might be several correct answers, you need to write one of them.
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Question:  A selective transcriptional induction system for mammalian cells based on Gal4 - estrogen receptor fusion proteins .

Answer: estrogen receptor


Question:  We have previously reported the first isolation of a c - myc - null cell line .

Answer: c - myc


Question:  The longest cDNA insert identified was 2 . 2 kb and encoded the entire 462 - amino acid open reading frame of rat CgA including an 18 - amino acid hydrophobic signal peptide .

Answer:
rat CgA