Yeh J, Danehy F T, Osathanondh R, Villa-Komaroff L
Department of Obstetrics, Gynecology and Reproductive Biology, Brigham and Women's Hospital, Boston, MA 02115.
Mol Cell Endocrinol. 1991 Sep;80(1-3):75-82. doi: 10.1016/0303-7207(91)90144-h.
Insulin-like growth factor-II (IGF-II) is postulated to have autocrine and/or paracrine functions in developing fetal tissues, but has never been reported in human fetal reproductive organs. The forms of IGF-II found in normal human serum include a 67 amino acid form and a variant form resulting from alternate splicing of the mRNA such that Ser-29 is replaced by four other amino acid residues. We studied the expression of mRNA encoding IGF-II in human fetal ovaries and uteruses of 10, 15, 19 and 22 weeks of gestation. By reverse transcription followed by polymerase chain reaction (PCR), we identified the co-expression of two mRNAs encoding IGF-II in all developmental stages of fetal ovaries and uteruses tested. One of the PCR amplified fragments was 9 nucleotides larger than the other. The PCR amplified ovarian and uterine DNA fragments were mapped by digestion with the restriction endonucleases AvaII and PvuII and both the IGF-II fragment and the larger IGF-II fragment produced the anticipated DNA patterns by gel electrophoresis. The PCR amplified DNA fragments were cloned and sequenced to confirm that the expressed mRNAs encoded IGF-II and variant IGF-II. We conclude that IGF-II and variant IGF-II mRNA co-expression occurs in the human fetal female genital tract and that the two forms of the growth factors may have physiologic roles in reproductive tract development.
胰岛素样生长因子-II（IGF-II）被认为在胎儿组织发育过程中具有自分泌和/或旁分泌功能，但在人类胎儿生殖器官中尚未见报道。在正常人血清中发现的IGF-II形式包括一种含67个氨基酸的形式和一种由mRNA可变剪接产生的变体形式，其中Ser-29被其他四个氨基酸残基取代。我们研究了妊娠10、15、19和22周的人类胎儿卵巢和子宫中编码IGF-II的mRNA的表达。通过逆转录随后进行聚合酶链反应（PCR），我们在所有测试的胎儿卵巢和子宫发育阶段均鉴定出两种编码IGF-II的mRNA的共表达。其中一个PCR扩增片段比另一个大9个核苷酸。用限制性内切酶AvaII和PvuII消化对PCR扩增的卵巢和子宫DNA片段进行图谱分析，IGF-II片段和较大的IGF-II片段在凝胶电泳中均产生预期的DNA图谱。将PCR扩增的DNA片段进行克隆和测序，以确认所表达的mRNA编码IGF-II和变体IGF-II。我们得出结论，IGF-II和变体IGF-II mRNA在人类胎儿女性生殖道中共表达，并且这两种形式的生长因子可能在生殖道发育中具有生理作用。
