Molecular and functional characterization of a novel gonadotropin-releasing-hormone receptor isolated from the common octopus (Octopus vulgaris)
Molecular and functional characterization of a novel gonadotropin-releasing-hormone receptor isolated from the common octopus (Octopus vulgaris)
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DOI：
10.1042/bj20051615
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发表时间：
2006-04-01
影响因子：
4.1
通讯作者：
Minakata, H
中科院分区：
文献类型：
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作者：
Kanda, A;Takahashi, T;Minakata, H
GnRH（促性腺激素释放激素）通过与特定受体的相互作用，在脊椎动物的生殖调节中起着关键作用。此前，我们从普通章鱼（octopus vulgaris）中分离出GnRH同源物oct-GnRH。在本研究中，我们从章鱼脑中鉴定出一种特异性的GnRH受体（oct-GnRHR）。Oct-GnRHR包括典型的脊椎动物GnRH受体的结构域和基序。内含子插入的位置在oct-GnRHR和脊椎动物GnRHR基因之间是保守的。南非爪蟾卵母细胞中表达的oct-GnRHR对oct-GnRH有反应，但对章鱼脑提取物的其他HPLC组分无反应。这些结果表明oct-GnRHR是oct-GnRH的真实受体。反转录PCR产物的Southern印迹显示oct-GnRHR mRNA广泛分布于中枢和周围神经系统以及一些外周组织中。原位杂交显示oct-GnRHR mRNA在自主神经功能、摄食、记忆和运动等相关区域表达。Oct-GnRH在章鱼卵巢和睾丸中诱导睾酮、孕酮和17 β -雌二醇的甾体生成，其中oct-GnRHR在卵巢和睾丸中大量表达。这些结果表明，oct-GnRH与其他脊椎动物一样，在章鱼中枢神经系统和外周组织中都是一种多功能的神经递质、神经调节剂和激素样因子，并且GnRH家族的结构和功能在章鱼和脊椎动物之间至少部分地具有进化上的保守性。
GnRH (gonadotropin-releasing hormone) plays a pivotal role in the regulation of reproduction in vertebrates through interaction with a specific receptor. Previously, we isolated a GnRH homologue, oct-GnRH, from the common octopus (Octopus vulgaris). In the present study, we have identified a GnRH receptor (oct-GnRHR) specific for oct-GnRH from Octopus brain. Oct-GnRHR includes domains and motifs typical of vertebrate GnRH receptors. The intron-inserted positions are conserved between oct-GnRHR and the chordate GnRHR genes. The oct-GnRHR expressed in Xenopus (South African clawed frog) oocytes was responsive to oct-GnRH, but not to any other HPLC fractions of the Octopus brain extract. These results show that oct-GnRHR is an authentic receptor for oct-GnRH. Southern blotting of reverse-transcription PCR products revealed that the oct-GnRHR mRNA was widely distributed in the central and peripheral nervous systems and in several peripheral tissues. In situ hybridization showed that oct-GnRHR mRNA was expressed in some regions involved in autonomic functions, feeding, memory and movement. Oct-GnRH was shown to induce steroidogenesis of testosterone, progesterone and 17 beta-oestradiol in Octopus ovary and testis, where oct-GnRHR was abundantly expressed. These results suggest that oct-GnRH, like its vertebrate counterparts, acts as a multifunctional neurotransmitter, neuromodulator and hormone-like factor, both in Octopus central nervous system and peripheral tissues, and that both structure and functions of the GnRH family are, at least partially, evolutionarily conserved between octopuses and chordates.