鳙鱼(Hypophthalmichthys nobilis)促性腺激素β亚基的克隆、表达和序列分析

Cloning,Expression and Sequence Analysis of two Gonadotropin Beta Subunits cDNA in the Bighead Fish (Hypophthalmichthys nobilis)

促性腺激素(Gonadotropin Hormone,GTH)是垂体合成和分泌的促进性腺发育成熟的一种重要的糖蛋白激素(Glycoprotein Hormones,GPHs).通过RT-PCR方法从鳙鱼(Hypophthalmichthys nobilis)脑垂体中克隆出两种促性腺激素β亚基,分别是促黄体素亚基(Luteinizing Hormone,LH)和促滤泡激素亚基(Follicle-stimulating Hormone,FSH).鳙鱼FSHβ亚基全长645bp,开放阅读框396bp,编码131个氨基酸(GenBank序列登录号:EF552360);LHβ亚基全长559bp,开放阅读框444bp,编码147个氨基酸(GenBank序列登录号:EF565164).根据鳙鱼与草鱼等鱼类及其他脊椎动物FSHβ和LHβ亚基的氨基酸序列分析表明:在鱼类中LHβ亚基具有高度保守性,而FSHβ亚基分化更快.用β-actin内参法从鳙鱼的垂体、下丘脑、心脏、肝脏和性腺等不同的组织,提取总RNA,用RT-PCR技术分析得出鳙鱼FSHβ和LHβ基因仅在垂体中特异性表达.

Two different Gonadotropin Hormone beta （GTHβ） subunits complementary DNA of Hypophthalmiehthys nobilis were amplified from total RNA in pituitary gland by reverse transcriptase polymerase chain reaction （RT-PCR）. The eDNA length of Follicle-stimulating Hormone （FSH） beta subunit is 645 bp,and the open reading frame 396 bp by encoding 131 amino acid. The eDNA length of Luteinizing Hormone （LH） beta subunit is 559 bp,and the open reading frame 444 bp by encoding 147 amino acid. They were submitted to GenBank,with accession No. EF552360 （FSH） and EF565164（LH） respectively. These two types of GTHβ subunits amino acid sequence show higher homology among fish as grass carp,blak carp,common carp,crucian carp. Amino acid sequence analysis showed LH-β subunit were higher conservative than FSHβ subunit in bighead carp. Expression analysis by RT-PCR showes that GTHβ subunit could be only expressed in pituitary.