Molecular mechanisms of onset of puberty in salmonids : regulation of GnRH receptor genes

鲑鱼青春期开始的分子机制：GnRH 受体基因的调节

• 批准号: 14540608
• 负责人: ANDO Hironori
• 金额: $ 2.24万
• 依托单位: KYUSHU UNIVERSITY (2004)Hokkaido University (2002-2003)
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for Scientific Research (C)
• 财政年份: 2002
• 资助国家: 日本
• 起止时间: 2002 至 2004
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-14540608/
• 关键词: Gonadotropin-releasing hormone; GnRH receptor; Reproduction; Spawning behavior; Hypothalamus; Pituitary; Salmon; Gene expression; 生殖腺刺激ホルモン

The onset of puberty is controlled by hypothalamus-pituitary system in vertebrates. However, molecular mechanisms of neuroendocrine regulation of puberty are unknown, particularly in lower vertebrates like fish. Salmonids are an interesting model for investigating the neuroendocrine mechanisms of puberty, because their sexual maturation progress slowly with seasons. We focused on regulation of expression of genes encoding gonadotropin-releasing hormone receptor(GnRH-R), which is a key molecule of responsiveness to GnRH. In salmonids, a single type I GnRH-R was originally identified in the brain of rainbow trout. We demonstrated in masu salmon that five different GnRH-R genes, termed msGnRH-R1,R2,R3,R4,and R5,are expressed in the brain, pituitary and other peripheral tissues with different pattern. A splicing variant of msGnRH-R1 is also expressed in these tissues. All these receptors are type I receptors, but are divided into two subtypes, one subtype (type Ia) includes R1,R2, and R3 a … More nd the other (type Ib) includes R4 and R5. The identity of nucleotide sequences among R1,R2 and R3 is 96-99%, while that of R4 and R5 is 81%. The identity between the two subtypes decreases to 59-71%. The effect of GnRH on gonadotropin (GTH) secretion may be attributed in part to changes in expression of GnRH-Rs. We therefore examined seasonal variations in expression of the five msGnRH-R genes in the pituitary during the reproductive cycle by real-time PCR. All five subtypes of msGnRH-R genes were expressed in the pituitary, although R4 mRNA was dominant. Interestingly, the expression patterns of five msGnRH-R genes differed among different subtypes. Among them, R4 mRNA increased only in the pre-spawning period, when GnRH stimulates expression of luteinizing hormone(LH) genes. These results suggest that R4 subtype is involved in the GnRH-induced LH synthesis. Other subtype mRNAs increased in different periods and may be related to other GnRH action in the pituitary such as GnRH-induced prolactin gene expression. To obtain more accurate information on the function of the multiple GnRH-R subtypes, cell type specific distribution of the GnRH-Rs in the pituitary needs to be determined. Less

在脊椎动物中，青春期的开始是由下丘脑-垂体系统控制的。然而，青春期神经内分泌调节的分子机制尚不清楚，特别是在鱼类等低等脊椎动物中。鲑科鱼类是研究青春期神经内分泌机制的一个有趣的模型，因为它们的性成熟随着季节的变化而缓慢。我们重点研究了促性腺激素释放激素受体（GnRH-R）基因表达的调控，GnRH-R是促性腺激素释放激素（GnRH）反应性的关键分子。在鲑鱼中，最初在虹鳟鱼的大脑中发现了单一的I型GnRH-R。我们证明，5个不同的GnRH-R基因，命名为msGnRH-R1，R2，R3，R4和R5，在马苏鲑鱼的脑，垂体和其他外周组织中以不同的模式表达。msGnRH-R1的剪接变体也在这些组织中表达。所有这些受体都是I型受体，但分为两种亚型，一种亚型（Ia型）包括R1、R2和R3 a ...更多信息 另一种（Ib型）包括R4和R5。R1、R2和R3的核苷酸序列同源性为96- 99%，而R4和R5的核苷酸序列同源性为81%。两种亚型之间的同一性降低至59- 71%。GnRH对促性腺激素（GTH）分泌的影响可能部分归因于GnRH-Rs表达的变化。因此，我们研究了季节性变化的五个msGnRH-R基因的表达在垂体在生殖周期的实时PCR。所有5种亚型的msGnRH-R基因表达的垂体，虽然R4 mRNA占主导地位。有趣的是，5个msGnRH-R基因的表达模式在不同亚型之间存在差异。其中，R4 mRNA仅在产卵前期增加，此时GnRH刺激促黄体生成素（LH）基因的表达。这些结果表明，R4亚型参与GnRH诱导的LH合成。其他亚型mRNA在不同时期增加，可能与垂体中的其他GnRH作用有关，如GnRH诱导的催乳素基因表达。为了获得更准确的信息，多种GnRH-R亚型的功能，细胞类型特异性分布的GnRH-R在垂体需要确定。少

项目成果

Abe S.et al.(他13名): "Development of molecular markers for genetic stock identification of chum salmon"Fisheries Science. (印刷中). (2003)

Abe S. 等人（其他 13 人）：“用于鲑鱼遗传资源鉴定的分子标记的开发”渔业科学（2003 年）。

サケ・マスの生態と進化(前川光司編)

鲑鱼和鳟鱼的生态和进化（前川浩司编辑）

• 发表时间: 2004
• 作者: 福島路生;亀山哲;福島路生(分担執筆)
• 通讯作者: 福島路生(分担執筆)

CREB in the pond snail Lymnaea stagnalis:: Cloning, gene expression, and function in identifiable neurons of the central nervous system

• DOI: 10.1002/neu.10296
• 发表时间: 2004-03-01
• 期刊: JOURNAL OF NEUROBIOLOGY
• 作者: Sadamoto, H;Sato, H;Ito, E
• 通讯作者: Ito, E

Functional organization of prepotic vasotocin and isotocin neurons in the brain of rainbow trout : central and neurohypophysial projections of single neurons.

虹鳟鱼大脑中前催产素和同催产素神经元的功能组织：单个神经元的中枢和神经垂体投射。

• 发表时间: 2004
• 期刊: Neuroscience 124
• 作者: Saito;D. et al.
• 通讯作者: D. et al.

Gonadotropin-releasing hormones modulate electrical activity of vasotocin and isotocin neurons in the brain of rainbow trout.

促性腺激素释放激素调节虹鳟大脑中的催产素和同催产素神经元的电活动。

• 发表时间: 2003
• 期刊: Neuroscience Letters 351
• 作者: Saito;D.et al.(他3名);Ando H.et al.;Jodo A.et al.;Saito D. et al.
• 通讯作者: Saito D. et al.