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:  Friend of GATA ( FOG ) proteins regulate GATA factor - activated gene transcription .

Answer: GATA factor


Question:  MHC tetramers , which constitute a labeled MHC - peptide ligand suitable for binding to the Ag - specific receptor on T cells , provide a novel approach for the detection and characterization of such rare cells .

Answer: MHC tetramers


Question:  The results suggest that M . tuberculosis can upregulate HIV - 1 expression in T cells and could thus have the potential to influence the pathogenesis of HIV - 1 infection .

Answer:
HIV - 1