生长激素/催乳素家族配体和受体成员在斑马鱼早期胚胎中的表达比较和交叉活性分析

THE COMPARATIVE EXPRESSION AND CROSS-INTERACTIONS OF GROWTH HORMONE/PROLACTIN LIGAND AND RECEPTOR FAMILY MEMBERS IN ZEBRAFISH EARLY EMBRYOS

为了进一步研究GH/PRL家族信号通路在鱼类早期胚胎发育中的作用,研究以斑马鱼为模型,通过Real-time PCR技术和原位杂交技术刻画并比较了GH/PRL家族成员及其受体家族成员在胚胎发育早期的表达模式。结果发现,在配体家族成员中,生长激素(Growth hormone,GH)和生长催乳素(Somatolactin,smtl)存在母源表达,在受体家族成员中,ghra、ghrb存在母源表达。利用荧光素酶分析spi2.1启动子活性的结果初步证明,在斑马鱼早期胚胎发育中,各配体家族成员与GHRa之间可以发生广泛的互作。这一系列结果对于我们认识GH/PRL家族信号通路在斑马鱼早期发育中的作用具有重要的指导意义。

Growth hormone (GH) is a member of the GH/Prolactin (PRL) protein super family. It is secreted by anterior pituitary and critically involved in the regulation of cell proliferation, differentiation and migration. Using RT-PCR (re-verse-transcription PCR), our previous study revealed that both gh and its receptor gene ghra (growth hormone receptor a) were maternally expressed in zebrafish. This suggested that the GH/GHR signaling pathway might play an important role at the early stage of zebrafish development. To further study the function of GH/PRL signaling pathway in zebrafish embryogenesis, here we characterized and compared the expression patterns of gh/prl and their receptor family members in early embryonic development using real-time PCR and in situ hybridization. We found that the ligand family mem-bers, gh and somatolactin (smtl), and the receptor gene family members, ghra and ghrb, were maternally expressed in zebrafish. The analysis of spi2.1 promoter activity indicated the cross-interaction between various ligand family mem-bers and GHRa in the early embryos of zebrafish. Our results demonstrated the important role of the GH/PRL family signaling pathway in the early development of zebrafish.