Iwamoto T, Taniguchi M, Asai N, Ohkusu K, Nakashima I, Takahashi M
Department of Immunology, Nagoya University School of Medicine, Japan.
Oncogene. 1993 Apr;8(4):1087-91.
We report the nucleotide sequence of the mouse ret proto-oncogene (proto-ret) and the deduced amino acid sequence. It encodes a transmembrane tyrosine kinase of 1115 amino acids that shows 83% homology with the human proto-Ret protein. The amino acid sequence revealed that the structures of the extracellular domain as well as the tyrosine kinase domain are similar in human and mouse proto-Ret proteins. Interestingly, the extracellular domains of both human and mouse proto-Ret proteins contain a cadherin-related sequence that is known to be important for Ca(2+)-dependent homophilic binding of the cadherins. When we examined transcription of the proto-ret gene in a variety of mouse tissues, it was detected in lymph nodes of C3H/HeJ-gld/gld mice and in normal mouse spinal cord. Furthermore, its transcription was found in the Neuro-2a mouse neuroblastoma cell line but not in 13 other rodent cell lines surveyed. Western blot analysis showed that proto-Ret proteins are expressed as 140-kDa and 160-kDa glycoproteins in Neuro-2a cells.
我们报道了小鼠原癌基因ret（proto-ret）的核苷酸序列及推导的氨基酸序列。它编码一个由1115个氨基酸组成的跨膜酪氨酸激酶，与人原癌基因Ret蛋白具有83%的同源性。氨基酸序列显示，人源和鼠源原癌基因Ret蛋白的胞外结构域以及酪氨酸激酶结构域相似。有趣的是，人源和鼠源原癌基因Ret蛋白的胞外结构域均包含一个与钙黏蛋白相关的序列，已知该序列对钙黏蛋白的钙离子依赖型同嗜性结合很重要。当我们检测原癌基因ret在多种小鼠组织中的转录情况时，在C3H/HeJ-gld/gld小鼠的淋巴结以及正常小鼠脊髓中检测到了它的转录。此外，在Neuro-2a小鼠神经母细胞瘤细胞系中发现了它的转录，但在所检测的其他13种啮齿动物细胞系中未发现。蛋白质免疫印迹分析表明，原癌基因Ret蛋白在Neuro-2a细胞中表达为140 kDa和160 kDa的糖蛋白。
