CHARACTERIZATION OF TST, THE EIGHTH MEMBER OF THE FGF GENE FAMILY

CDNA在哺乳动物细胞中的异位表达已被广泛应用 分离编码生长因子及其受体的基因。 小鼠睾丸cDNA文库导入NIH/3T3成纤维细胞的研究 结果分离到几个高滴度的cDNA克隆 改造产能。其中一个克隆的序列。TST。A 1.6 Kb基因，编码208个氨基酸的蛋白质。 揭示了Tst是成纤维细胞生长因子的第八个成员 (FGFs)基因家族。表达Tst的NIH/3T3细胞的条件培养液 刺激成纤维细胞DNA合成。上皮细胞和神经胶质细胞 细胞。表明有丝分裂活性的广谱。Tst基因的cDNA 从成年小鼠睾丸中提取的RNA中检测到1.6kB的mRNA。但不是 在从小鼠肝脏中分离的RNA中。大脑。心脏或肾脏。核糖核酸酶 保护性分析表明，Tst基因的丰度是 在小鼠胚胎发育的第11天和第13天最高。 此外。通过对人成纤维细胞生长因子-8基因的筛选，获得了人成纤维细胞生长因子-8的部分基因 含Tst基因的睾丸cDNA文库。

The ectopic expression of cDNAs in mammalian cells has been widely used to isolate genes encoding growth factors and their receptors. Transfection of a mouse testis cDNA library into NIH/3T3 fibroblasts resulted in the isolation of several cDNA clones with high titer transforming capacity. The sequence of one of these clones. Tst. a 1.6 kB cDNA with an open reading frame encoding a protein of 208 amino acids. revealed that Tst was the eighth member of the fibroblast growth factor (FGF) gene family. Conditioned medium from NIH/3T3 cells expressing Tst stimulated DNA synthesis in fibroblasts. epithelial cells and glial cells. indicating a broad spectrum of mitogenic activity. The Tst cDNA detected a 1.6 kB mRNA in RNA isolated from adult mouse testis. but not in RNA isolated from mouse liver. brain. heart or kidney. Ribonuclease protection analysis demonstrated that the abundance of Tst mRNA was highest during embryonic day 11 and 13 of mouse embryonic development. In addition. a partial human FGF-8 cDNA was isolated by screening a human testis cDNA library with the Tst cDNA.