Studies of the function and gene of somatolactin, a new pituitary hormone

新型垂体激素生长抑素的功能及基因研究

• 批准号: 03405007
• 负责人: KAWAUCHI Hiroshi
• 金额: $ 12.1万
• 依托单位: Kitasato University
• 依托单位国家: 日本
• 项目类别: Grant-in-Aid for General Scientific Research (A)
• 财政年份: 1991
• 资助国家: 日本
• 起止时间: 1991 至 1993
• 项目状态: 已结题
• 来源: https://kaken.nii.ac.jp/grant/KAKENHI-PROJECT-03405007/
• 关键词: Somatolactin; pititary hormone; acid-base balance; gene; gene expression; plasma lebel; calcium regulation; fat metabolism; 一次構造; 遺伝子構造; ソマトメジン様ペプチド; 脂肪代謝; カルシウム代謝; シロサケ; 下重体ホルモン; ラジオイムノアッセイ; 太西洋タラ; ヒラメ

The goal of the roject is to stablish a newy fund pituitary protein, somatolactin, as a tropic hormone. Somatolactin (SL) is a new hypophysial member of growth hormone (GH) and prolactin (PRL) family of teleosts. SLs of Atantic cod, flunder, salmonids, gilthead, carp, and channel catfsh, and SLcDNAs of flunder, Atantic cod, and chum salmon have been identified. Comparison of the SL sequences so far analyzed indicates that this protein is highly conserved, more so than the GHs from the corresponding species. Immunhistochemistry with a specific antiserum to cod SL revealed that SL is present in periodic-acid-Shiff-positive cells of the ars intermeda in cod and mst other teleost species, and in chromophoic cells of the pars intermedia in salmonids. By an eectron-microscopic immunohistochemistry protein A-gold complex s localized mostly on the secretory granules of these cels of rainbow trout. A homologous radio-immunoassay specific for salmon SL was deeloped and validated. Increases of plasma SL levels have been bserved, during the final year of reroductive maturation of coho slmn, after transfer rainbow trout from Ca-rich fresh water to fresh water, and after exposure rainbow trout to acidic waer. These findings suggest that SL regulates reproduction, Ca-metabolism, and acid-base balance. Salmon SL gene was comprised of five exones as in the case of mammalian GH/PRL gees, but was ulike salmnid GH genes, which have 6 exones. Upstream from the transcriptional initiation site were found one TATA box and four consensus sequences corresponding to the Pit-1 binding element, which is known to be essential to expression of mammalian GH and PRL genes. Salmon Pit-1 mRNA was found to encode a 365 amino acid protein, which was 74 residues larger than that of rat Pit-1. Using antibody against chum samon Pit-1, this protein was shwn to be located in the nuclei in the SL-producing cells in the pars intermedia. In experments of cotransection into HeLa cells, Pit-1 enhanced the promo

本课题的目的是建立一种新的垂体促生长激素的基础蛋白--生长抑素。生长激素（SL）是硬骨鱼类垂体生长激素（GH）和催乳素（PRL）家族的新成员。已经鉴定了大西洋鳕鱼、比目鱼、鲑科鱼、金头鱼、鲤鱼和海峡鲶鱼的SL，以及比目鱼、大西洋鳕鱼和鲑鱼的SLcDNA。SL序列的比较表明，这种蛋白质是高度保守的，比相应物种的GH。免疫组化与鳕鱼SL的特异性抗血清显示，SL是目前在ars intermeda在鳕鱼和mst其他硬骨鱼类，并在发色细胞的pars intermedia在鲑。电镜免疫组化结果显示，A蛋白-金复合物主要定位于虹鳟鱼体的分泌颗粒上。开发并验证了鲑鱼SL的同源放射免疫分析法。在银鲫生殖成熟的最后一年，将虹鳟鱼从富钙淡水转移到淡水中，以及暴露于酸性水后，均观察到血浆SL水平的升高。这些结果表明，SL调节生殖，钙代谢和酸碱平衡。鲑鱼SL基因与哺乳动物GH/PRL β基因一样由5个外显子组成，而鲑鱼GH基因与哺乳动物GH/PRL β基因一样由6个外显子组成。在转录起始位点的上游发现了一个TATA盒和四个对应于Pit-1结合元件的共有序列，已知Pit-1结合元件对哺乳动物GH和PRL基因的表达是必需的。鲑鱼Pit-1 mRNA编码一个由365个氨基酸组成的蛋白质，比大鼠Pit-1基因编码的蛋白质多74个氨基酸。用抗人Pit-1的抗体证明该蛋白定位于中间部SL产生细胞的细胞核内。在共转染HeLa细胞的实验中，Pit-1增强了HeLa细胞的促凋亡作用，

项目成果

Kaneko,T.,Hasegawa,S.,Yada,T.,Hirano,T.: "Pituitary of“Cobalt"variant of the rainbow trout separated from the hypothalamus lacks most pars intermedial and neurohypophysial tissue." Gen.Comp.Endocrinol.92. 31-40 (1993)

Kaneko, T.、Hasekawa, S.、Yada, T.、Hirano, T.：“与下丘脑分离的“钴”变种的垂体缺乏大部分中间部和神经垂体组织。” 92. 31-40 (1993)

Ono,M.,Harigai,T.,Kaneko,T.,Sato,T.,Ihara,I.,Kawauchi,H.: "Pit-1/GHF-1 involvement in the gene expression of somatolactin." Mol.Endocrinol.8. 109-115 (1994)

Ono,M.、Harigai,T.、Kaneko,T.、Sato,T.、Ihara,I.、Kawauchi,H.：“Pit-1/GHF-1 参与生长抑素基因表达。”

Kawauchi,H.: "Trends in Comparative Physiology and Biochemistry" University of Tokyo,Tokyo, 6 (1992)

Kawauchi,H.：“比较生理学和生物化学的趋势”东京大学，东京，6（1992）

Igarashi.A., Noso, T., Kawauchi, H.: "The complete amino acid sequence of chum salmon (Oncorhynchus Keta) somatolactin." Int.J.Peptide Protein Res.(in preparation).

Igarashi.A.、Noso, T.、Kawauchi, H.：“鲑鱼 (Oncorhynchus Keta) 生长激素的完整氨基酸序列。”

川内浩司、Rand-Weaver,M.,: "新しい脳下垂体ホルモン、ソマトラクチン" 生化学. 63. 1205-1209 (1991)

K. Kawauchi, Rand-Weaver, M.，“一种新的垂体激素，生长抑素”，《生物化学》63. 1205-1209 (1991)。