Lee S J
Carnegie Institution of Washington, Department of Embryology, Baltimore, Maryland 21210.
Mol Endocrinol. 1990 Jul;4(7):1034-40. doi: 10.1210/mend-4-7-1034.
A cDNA clone encoding a new member (designated GDF-1) of the transforming growth factor-beta (TGF beta) superfamily was isolated from a library prepared from day 8.5 mouse embryos. The nucleotide sequence of GDF-1 predicts a protein of 357 amino acids with a mol wt of 38,600. The sequence contains a pair of arginine residues at positions 236-237, which is likely to represent a site for proteolytic processing. The C-terminus following the presumed dibasic cleavage site shows significant homology with the known members of the TGF beta superfamily, matching the other family members at all of the invariant positions, including the seven cysteine residues with their characteristic spacing. GDF-1 is most homologous to Xenopus Vg-1 (52%), but is not likely to be the murine homolog of Vg-1. In vitro translation experiments were consistent with GDF-1 being a secreted glycoprotein. Genomic Southern analysis indicated that GDF-1 may be highly conserved across species. These results suggest that GDF-1 is most likely an extracellular factor mediating cell differentiation events during embryonic development.
从第8.5天的小鼠胚胎制备的文库中分离出一个编码转化生长因子-β（TGFβ）超家族新成员（命名为GDF-1）的cDNA克隆。GDF-1的核苷酸序列预测其为一个由357个氨基酸组成、分子量为38,600的蛋白质。该序列在236 - 237位含有一对精氨酸残基，这可能代表一个蛋白水解加工位点。假定的双碱性切割位点之后的C末端与TGFβ超家族的已知成员显示出显著的同源性，在所有不变位置与其他家族成员匹配，包括具有特征性间隔的七个半胱氨酸残基。GDF-1与非洲爪蟾Vg-1的同源性最高（52%），但不太可能是Vg-1的小鼠同源物。体外翻译实验与GDF-1是一种分泌性糖蛋白的结论一致。基因组Southern分析表明GDF-1在物种间可能高度保守。这些结果提示GDF-1很可能是一种在胚胎发育过程中介导细胞分化事件的细胞外因子。
