Seed J, Olwin B B, Hauschka S D
Department of Biochemistry, University of Washington, Seattle 98195.
Dev Biol. 1988 Jul;128(1):50-7. doi: 10.1016/0012-1606(88)90265-5.
A growth factor with properties very similar to fibroblast growth factor (FGF) was detected in the yolk and white of unfertilized chick eggs, and in the limb bud and bodies of Day 2.5 (stage 18)-13 chick embryos using two complementary and highly sensitive biological assays-competition of 125I-a-FGF binding to the FGF receptors of 3T3 cells and stimulation of DNA synthesis in MM14 cells, a permanent mouse skeletal muscle cell line that is dependent upon FGF for proliferation. Further evidence of the similarity of this growth factor to FGF is provided by the finding that biological activity is lost when the material is bound to a heparin-Sepharose column and restored upon elution with 2.5 M NaCl; the 2.5 M NaCl fraction from Day 12 embryos contains several polypeptides of apparent molecular weights 12,500-17,500. The level of FGF in the embryonic chick body is fairly constant between Days 2.5 and 6 (stages 18-29), ranging between 1 and 2 ng FGF/mg protein; but thereafter the level increases so that by Day 13 the body contains about 15 ng FGF/mg protein. In contrast, the level of FGF in the limb but is higher than that in the rest of the body until Day 5 (stage 27); it then undergoes a transient decrease between Days 6 and 7, after which it increases but remains below the level observed in the remainder of the body.
在未受精的鸡蛋蛋黄和蛋清中，以及在第2.5天（第18阶段）至第13天的鸡胚的肢芽和体内，利用两种互补且高度灵敏的生物学检测方法——125I-α-成纤维细胞生长因子（FGF）与3T3细胞的FGF受体结合的竞争试验，以及在MM14细胞（一种依赖FGF进行增殖的永久性小鼠骨骼肌细胞系）中刺激DNA合成，检测到了一种性质与成纤维细胞生长因子（FGF）非常相似的生长因子。该生长因子与FGF相似性的进一步证据来自以下发现：当该物质与肝素-琼脂糖柱结合时，生物活性丧失，而用2.5M NaCl洗脱后生物活性恢复；来自第12天胚胎的2.5M NaCl组分包含几种表观分子量为12,500 - 17,500的多肽。在鸡胚体内，FGF的水平在第2.5天至第6天（第18 - 29阶段）之间相当恒定，范围为1至2 ng FGF/ mg蛋白质；但此后水平升高，以至于到第13天时，体内含有约15 ng FGF/ mg蛋白质。相比之下，直到第5天（第27阶段），肢体中FGF的水平高于身体其他部位；然后在第6天至第7天之间经历短暂下降，之后又升高，但仍低于身体其他部位观察到的水平。
