Tissue preferential expression of estrogen receptor gene in the marine snail, Thais clavigera
Tissue preferential expression of estrogen receptor gene in the marine snail, Thais clavigera
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DOI：
10.1016/j.ygcen.2006.03.016
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发表时间：
2006-09-15
影响因子：
2.7
通讯作者：
Takahashi, Yuji
中科院分区：
文献类型：
--
作者：
Kajiwara, Masaaki;Kuraku, Shigehiro;Takahashi, Yuji
性类固醇激素广泛存在于软体动物中，实验表明性类固醇激素在软体动物性别决定、性腺组织成熟和配子发生中的重要作用。然而，性类固醇在无脊椎动物中的信号通路尚未阐明。为了深入了解性类固醇信号在软体动物中的机制，我们，因此，试图从前鳃类软体动物Thais clavigera分离软体动物雌激素受体。提取了棒形刺水蚤（Tclavigera）（软体动物门、腹足类、前鳃类）脑神经节的RNA，设计了脊椎动物雌激素受体保守氨基酸序列的简并引物。用脑RNA和简并引物进行PCR扩增，然后用5 '-和3'-RACE鉴定编码T clavigera雌激素受体1（tcER 1）的cDNA。推导的氨基酸序列显示93%的DNA结合结构域和72%的同源性，在配体结合结构域相比，Aesthesia雌激素受体。报告基因测定显示tcER 1具有组成性活性，对雌激素无反应。tcER 1 mRNA水平的定量分析表明，在卵巢中的优先表达。此外，大脑神经节表达tcER 1在一个高水平的春天，随后在以后的季节卵巢扩大。这些结果表明，tcER 1在T. clavigera。(c)2006年爱思唯尔公司All rights reserved.
Sex steroid hormones have been widely detected in molluscs, and experiments have shown the importance of sex steroids in sex determination, gonadal tissue maturation and gametogenesis. Nevertheless, the signaling pathways of sex steroids in invertebrates have not yet been elucidated. In order to gain insights into the mechanism of sex steroid signaling in molluscs, we have, therefore, tried to isolate molluscan estrogen receptors from the prosobranch mollusc Thais clavigera. Cerebral ganglia of T clavigera (Mollusca, Gastropoda, Prosobranchia) were subjected to RNA extraction, and degenerate primers for amino acid sequences conserved in vertebrate estrogen receptors were designed. PCR amplification using cerebral RNA and degenerate primers followed by 5'- and 3'-RACE identified the cDNA encoding T clavigera estrogen receptor 1 (tcER1). The deduced amino acid sequence showed 93% identity in the DNA-binding domain and 72% identity in the ligand binding domain when compared to Aplysia estrogen receptor. Reporter gene assay revealed that tcER1 is constitutively active and unresponsive to estrogen. Quantitative analysis of the tcER1 mRNA level demonstrated the preferential expression in the ovary. Furthermore, cerebral ganglia expressed tcER1 at a high level in the spring followed by subsequent enlargement of the ovary in later seasons. These results suggest importance of tcER1 in the seasonal development of reproductive organs in T. clavigera. (c) 2006 Elsevier Inc. All rights reserved.