Thompson A D, Braun B S, Arvand A, Stewart S D, May W A, Chen E, Korenberg J, Denny C
Molecular Biology Institute, University of California, Los Angeles 90095, USA.
Oncogene. 1996 Dec 19;13(12):2649-58.
The EWS/FLI1 fusion protein is created by the translocation between chromosomes 11 and 22 that appears in most Ewing's sarcomas. This chimeric protein has been demonstrated to be an aberrant transcription factor. Genes up regulated by EWS/FLI1 but not by full-length FLI1 were identified by representational difference analysis (RDA). We have characterized a novel gene, EWS/FLI1 activated transcript 2 (EAT-2) that was cloned from a murine cDNA library using a differentially expressed RDA fragment. EAT-2 expression is seen within 4-8 h of EWS/FLI1 induction. Its expression correlates with transformation of NIH3T3 cells by chimeric proteins related to EWS/FLI1 but not by unrelated genes. EAT-2 is expressed in normal murine tissues and contains a unique but biochemically functional SH2 domain. An homologous sequence in the human genome has been identified and mapped to chromosome 1q22. Human EAT-2 transcripts were identified by reverse transcriptase-polymerase chain reaction (RT-PCR) in Ewing's sarcoma cell tumour cell lines. EAT-2's unique structure and correlation with transformation make it a candidate for playing a role in the transformation of NIH3T3 cells and the oncogenesis of Ewing's sarcoma.
EWS/FLI1融合蛋白由11号和22号染色体之间的易位产生，这种易位出现在大多数尤因肉瘤中。已证实这种嵌合蛋白是一种异常转录因子。通过代表性差异分析（RDA）鉴定了由EWS/FLI1上调但不由全长FLI1上调的基因。我们鉴定了一个新基因，EWS/FLI1激活转录本2（EAT-2），它是利用差异表达的RDA片段从鼠cDNA文库中克隆出来的。在诱导EWS/FLI1后4-8小时内可观察到EAT-2的表达。其表达与EWS/FLI1相关嵌合蛋白而非无关基因对NIH3T3细胞的转化相关。EAT-2在正常鼠组织中表达，并含有一个独特但具有生化功能的SH2结构域。已在人类基因组中鉴定出同源序列并将其定位到1号染色体q22区域。通过逆转录聚合酶链反应（RT-PCR）在尤因肉瘤细胞系中鉴定出人类EAT-2转录本。EAT-2独特的结构及其与转化的相关性使其成为在NIH3T3细胞转化和尤因肉瘤肿瘤发生中发挥作用的候选分子。
