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:  These data suggest that the secreted , truncated receptor encoded by the 2 . 6 - kb c - erbB transcript can bind to TGF alpha and may play an important growth - regulatory function in vitro .

Answer: TGF alpha


Question:  Although polyubiquitin chains linked through Lys ( 29 ) of ubiquitin have been implicated in the targeting of certain substrates to proteasomes , the signaling properties of these chains are poorly understood .

Answer: polyubiquitin chains


Question:  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 .

Answer:
G - proteins