Lee E K, Kehrli M E, Taylor M J
Department of Veterinary Physiology and Pharmacology, Iowa State University, Ames 50010, USA.
Vet Immunol Immunopathol. 1998 Feb 27;61(2-4):379-85. doi: 10.1016/s0165-2427(97)00136-0.
Tumor necrosis factor (TNF) is a multipotent cytokine produced by activated macrophages and lymphocytes and its activity is mediated by specific cell surface receptors, TNF-RI and TNF-RII. We have isolated and analyzed a cDNA encoding bovine TNF-RI gene and compared it with known TNF-RI sequences from other species. The cDNA sequence for the coding region of bovine TNF-RI shows 80% homology with porcine TNF-RI and 77% with human TNF-RI. The cDNA sequence of bovine TNF-RI codes for 471 amino acids and shows 75% and 67% identity with the amino acid sequences of porcine TNF-RI and human TNF-RI, respectively. The predicted bovine TNF-RI amino acid sequence consists of a signal peptide, an extracellular domain, a transmembrane region and a cytoplasmic tail. The extracellular region contains four repeated cysteine rich domains, which are conserved in all species. Northern blot results show that bovine TNF-RI gene is expressed in neutrophils and mononuclear leukocytes.
肿瘤坏死因子（TNF）是一种由活化的巨噬细胞和淋巴细胞产生的多效细胞因子，其活性由特异性细胞表面受体TNF-RI和TNF-RII介导。我们已经分离并分析了编码牛TNF-RI基因的cDNA，并将其与来自其他物种的已知TNF-RI序列进行了比较。牛TNF-RI编码区的cDNA序列与猪TNF-RI的同源性为80%，与人类TNF-RI的同源性为77%。牛TNF-RI的cDNA序列编码471个氨基酸，与猪TNF-RI和人类TNF-RI的氨基酸序列的同一性分别为75%和67%。预测的牛TNF-RI氨基酸序列由一个信号肽、一个细胞外结构域、一个跨膜区域和一个细胞质尾组成。细胞外区域包含四个重复的富含半胱氨酸的结构域，这些结构域在所有物种中都是保守的。Northern印迹结果表明，牛TNF-RI基因在中性粒细胞和单核白细胞中表达。
