Nedwin G E, Naylor S L, Sakaguchi A Y, Smith D, Jarrett-Nedwin J, Pennica D, Goeddel D V, Gray P W
Nucleic Acids Res. 1985 Sep 11;13(17):6361-73. doi: 10.1093/nar/13.17.6361.
Human Tumor Necrosis Factor and Lymphotoxin are cytotoxic proteins which have similar biological activities and share 30 percent amino acid homology. The single copy genes which encode these proteins share several structural features: each gene is approximately three kilobase pairs in length and is interrupted by three introns. In addition, these genes are closely linked and have been mapped to human chromosome 6. However, only the last exons of both genes, which code for more than 80 percent of each secreted protein, are significantly homologous (56 percent).
人类肿瘤坏死因子和淋巴毒素是具有相似生物学活性且氨基酸同源性为30%的细胞毒性蛋白。编码这些蛋白的单拷贝基因具有几个结构特征:每个基因长度约为三千碱基对,被三个内含子中断。此外,这些基因紧密连锁,已被定位到人类6号染色体上。然而,只有两个基因的最后外显子具有显著同源性(56%),它们编码每种分泌蛋白的80%以上。