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胰岛素样生长因子-Ⅰ(insulin-like growth factor Ⅰ,IGF-Ⅰ)是脊椎动物生长发育的重要调控因子,其生物学功能主要通过与其特异的膜受体(IGF-Ⅰ receptor,IGF-IR)结合而调节。因此,IGF-Ⅰ及其受体表达特征的分析对于阐述IGF系统调控的发育过程具有重要的意义。本研究采用荧光实时PCR方法,以不同发育时期的牙鲆(Paralichthys olivaceus)胚胎为材料,分析了胰岛素样生长因子-Ⅰ(IGF-Ⅰ)及其两种受体基因在鱼类胚胎发育过程中的表达图式。结果显示,牙鲆IGF-Ⅰ、IGF-IR-1和IGF-IR-2基因均有母源转录本,且各基因的表达在胚胎发育的不同阶段具有明显的发育性变化。IGF-Ⅰ基因在早期胚胎发育阶段仅有少量的mRNA存在,而合子基因的表达在晶体出现至出膜前阶段逐步增加。两种IGF-Ⅰ受体基因则展现出迥然不同的表达时序。IGF-IR-1基因在受精卵、卵裂及囊胚期的早期胚胎发育中有相对较少的转录本,至原肠期其合子基因强烈表达,且在神经胚、晶体出现、心跳和出膜前各阶段均有高量的表达;相反,IGF-IR-2基因在受精卵至原肠期的早期胚胎中有丰富的转录本,但合子基因的表达在后期胚胎形成中却相对降低,暗示了二者可能在调节牙鲆胚胎发育中起着不同的作用。
Insulin-like growth factor-Ⅰ (IGF-Ⅰ) is an important regulator of vertebrate growth and development, and its biological function is mainly related to its specific membrane receptor (IGF-Ⅰ receptor, IGF-IR) Combined with regulation. Therefore, the analysis of the expression characteristics of IGF-I and its receptors is of great significance to elucidate the developmental process of IGF regulation. In this study, fluorescence real-time PCR was used to detect the expression of insulin-like growth factor-I (IGF-Ⅰ) and its two receptor genes during the embryonic development of fish (Paralichthys olivaceus) at different developmental stages Expressions of expression. The results showed that there were maternal transcripts of IGF-I, IGF-IR-1 and IGF-IR-2 in flounder, and the expression of each gene had obvious developmental changes in different stages of embryo development. IGF-Ⅰ gene in the early embryonic development stage only a small amount of mRNA exists, and zygotic gene expression in the crystal appeared to the pre-membrane phase gradually increased. The two IGF-I receptor genes display very different timing of expression. The IGF-IR-1 gene has relatively few transcripts in fertilized egg, cleavage and early embryo development at blastula stage, and its zygotic gene is strongly expressed in the intestine during neurogenic stage. On the contrary, IGF-IR-2 gene had rich transcripts in the early embryos of the fertilized egg up to the intestine, but the expression of zygotic gene was relatively decreased in the late embryogenesis, Suggesting that both may play different roles in the regulation of Japanese flounder embryonic development.