Velcich A, Delli-Bovi P, Mansukhani A, Ziff E B, Basilico C
Department of Biochemistry, New York University School of Medicine, New York 10016.
Oncogene Res. 1989;5(1):31-7.
Utilizing F9 embryonal carcinoma cells as a model system for early mammalian development, we have studied the pattern of expression of the endogenous murine homolog of the human K-fgf/hst oncogene, which encodes a new member of the fibroblast growth factors (FGFs) family. The K-fgf mRNA is expressed in undifferentiated F9 cells and its level becomes undetectable upon the induction of differentiation. Furthermore, a growth-promoting activity with properties identical to those of K-FGF is present in the conditioned medium of F9 cells, but absent in that of differentiated cells. Shut-off of K-fgf expression is mediated at the transcriptional level. The acidic FGF gene is also expressed in undifferentiated F9 cells and down modulated once differentiation is induced. In contrast, int-2, another member of the FGF gene family, is transcriptionally induced in differentiated F9 cells. Our data suggest that single members of the FGF gene family may perform distinct functions in vivo, and that the physiological role of K-FGF may be related to early development.
利用F9胚胎癌细胞作为早期哺乳动物发育的模型系统，我们研究了人类K-fgf/hst癌基因的内源性小鼠同源物的表达模式，该基因编码成纤维细胞生长因子（FGFs）家族的一个新成员。K-fgf mRNA在未分化的F9细胞中表达，诱导分化后其水平变得检测不到。此外，F9细胞的条件培养基中存在一种生长促进活性，其性质与K-FGF相同，但分化细胞的条件培养基中不存在。K-fgf表达的关闭是在转录水平介导的。酸性FGF基因也在未分化的F9细胞中表达，诱导分化后被下调。相比之下，FGF基因家族的另一个成员int-2在分化的F9细胞中被转录诱导。我们的数据表明，FGF基因家族的单个成员可能在体内发挥不同的功能，并且K-FGF的生理作用可能与早期发育有关。
