SH2 Domain Containing Protein 1B (SH2D1B)

EAT2 regulates signal transduction through receptors expressed on the surface of antigen-presenting cells. The deduced 132-amino acid Eat2 protein consists principally of an SH2 domain flanked by short N and C termini. Northern blot analysis detected a major transcript of about 1.5 kb in mouse spleen and lung, and these tissues also expressed larger transcripts at weaker levels. A band of about 1.2 kb was expressed at low levels in liver, skeletal muscle, and kidney. No expression was detected in heart, brain, and testis. RT-PCR detected EAT2 transcripts in normal human peripheral blood lymphocytes and thymus. Expression was also detected in Ewing sarcoma cell lines containing either EWS/FLI1 or EWS/ERG fusion genes, as well as in some tumor cell lines without the EWS/FLI1 fusion gene.