岩原鲤促性腺激素基因的克隆和组织表达差异

Cloning and Gene Expression of cDNA for the GonadotropinHormone in Rock Carp(Procypris rabaudi)

通过RT-PCR技术从岩原鲤(Procypris rabaudi)卵巢组织中克隆了促性腺激素GtHα、FSHβ、LHβ3个亚基的mRNA序列。GtHα亚基开放阅读框长357 bp,编码118个氨基酸残基,第1～23个氨基酸为信号肽。FSHβ亚基开放阅读框长393 bp,编码130个氨基酸残基,第1～22个氨基酸为信号肽。LHβ亚基开放阅读框长444 bp,编码147个氨基酸残基,第1～28个氨基酸为信号肽。氨基酸序列比对结果表明,GtHα亚基在近缘物种间比较保守,其氨基酸序列的相似性要高于FSHβ和LHβ亚基。通过Real-time fluorescent quantitative PCR(FQ-PCR)分析发现,GtHα亚基在检测的6种组织中均有表达,卵巢中的表达量极高,肝、脑、心、垂体和肌肉中表达量依次降低;FSHβ亚基在除肌肉外的其余5种组织中均有表达,卵巢中的表达量最高,脑和心中表达量次之,肝和垂体的表达量明显偏低;LHβ亚基只在卵巢和垂体中表达,卵巢中的表达量要明显高于垂体。

The gonadotropin （GtH） subunit GtHα, FSHB and LHβ eDNAs were cloned from ovary of rock carp （Procypris rabaudi） through RT-PCR. The nucleotide sequences of GtHct, FSHβ and LHβ are 357, 393 and 444 base pairs （bp） in length, respectively. The open reading frame （ORF） of GtHα encodes 118 amino acid residues of peptide, and the first 23 amino acids comprise a signal peptide. The ORF of FSHβ encodes 130 amino acid residues of peptide, and the first 22 amino acids comprise a signal peptide. The ORF of LHβ encodes 147 amino acid residues of peptide, and the first 28 amino acids comprise a signal peptide. Sequence similarity of GtHα subunit between rock carp and other fish species or vertebrates are much higher than that of FSHβ and LHβ subunits, showing that GtHα subunit is more conservative than FSHβ and LHβ subunits. Expression analysis by real-time fluorescent quantitative PCR （FQ-PCR） revealed that GtHα was ubiquitously expressed in all six tissues examined ; the highest level of GtHα transcript was detected in ovary ; the expressionlevels in liver, brain, heart, pituitary and muscle descended in order. FSHβ was expressed in all tissues except for muscle; the FSHβ mRNA was abundantly expressed in ovary, to a lesser extent in brain and heart, at low level in liver and pituitary. LHβ was only expressed in ovary and pituitary, and the expression in ovary was significantly higher than that in pituitary.