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胰岛素样生长因子Ⅱ(IGF-Ⅱ)是一种多肽,其结构类似于胰岛素、胰岛素样生长因子Ⅰ和松驰激素。尽管几种胎儿组织均合成IGF-Ⅱ,并可能刺激胎儿生长,但其作用仍不十分清楚。肝脏中 IGF-Ⅱ的转录类型既是组织特异性的,又取决于发育阶段。实际上,业已鉴别出三种主要的 IGF-ⅡmRNAs(6,5.3和5kb),它们由截然不同的启动子通过不同的拼接方式产生。在肝、肾、横纹肌等几种人类胎儿组织中都发现高水平的IGF-ⅡmRMA,而成人同样组织中则较低。某些胚性肿瘤,如 Wilms 肿瘤、横纹肌肉瘤,IGF-Ⅱ
Insulin-like growth factor II (IGF-II) is a polypeptide whose structure is similar to that of insulin, insulin-like growth factor I, and relaxing hormone. Although several fetal tissues synthesize IGF-II and may stimulate fetal growth, its role remains unclear. The transcriptional type of IGF-II in the liver is both tissue-specific and developmental. In fact, three major IGF-II mRNAs (6, 5.3 and 5 kb) have been identified, which are generated by distinct splicing methods from distinct promoters. High levels of IGF-IImRMA were found in several human fetal tissues such as liver, kidney, and striated muscle, while adults were lower in the same tissue. Some embryonal tumors, such as Wilms tumor, rhabdomyosarcoma, IGF-II