Matòsková B, Wong W T, Nomura N, Robbins K C, Di Fiore P P
IEO, European Institute of Oncology, Milan, Italy.
Oncogene. 1996 Jun 20;12(12):2679-88.
We isolated a cDNA encoding a protein, RN-tre, which shows homology to the N-terminus of the tre oncogene product and has SH3-binding ability as well as an evolutionarily conserved domain, termed TrH, with protein-binding ability in vitro. In the present study, we identify the product of the RN-tre gene as a 97-100 kDa protein. We demonstrate stable association in vivo and in vitro between RN-tre and eps8, mediated by the SH3 domain of the latter. In vitro, RN-tre displayed remarkable preference for binding to the eps8-SH3, as compared to eight other SH3s. The Kd for the in vitro interaction between RN-tre and eps8-SH3 was between 10(-8) and 10(-7) M. A role for RN-tre in cell proliferation was suggested by the finding that a C-terminal truncated mutant was able to confer proliferative advantage and reduced serum-requirement to NIH3T3 fibroblasts. Finally, comparison of the structure and biological activities of RN-tre and of the tre oncogene product, provided insight into the mechanism of oncogenic activation of tre.
我们分离出了一个编码蛋白质RN-tre的cDNA，该蛋白质与tre癌基因产物的N端具有同源性，具有SH3结合能力以及一个在体外具有蛋白质结合能力的进化保守结构域，称为TrH。在本研究中，我们确定RN-tre基因的产物是一种97 - 100 kDa的蛋白质。我们证明了RN-tre与eps8在体内和体外均存在稳定的结合，这种结合由eps8的SH3结构域介导。在体外，与其他八个SH3相比，RN-tre对eps8-SH3的结合表现出显著的偏好。RN-tre与eps8-SH3体外相互作用的解离常数在10^(-8)至10^(-7) M之间。通过发现C端截短的突变体能够赋予NIH3T3成纤维细胞增殖优势并降低血清需求，提示了RN-tre在细胞增殖中的作用。最后，对RN-tre和tre癌基因产物的结构及生物学活性进行比较，为tre致癌激活机制提供了深入了解。
