Chopineau M, Stewart F
Babraham Institute, Cambridge, UK.
J Mol Endocrinol. 1996 Feb;16(1):9-13. doi: 10.1677/jme.0.0160009.
Reverse transcription-PCR was used to clone the coding region of the donkey (Equus asinus) glycoprotein hormone alpha-subunit transcript from pituitary gland RNA. The donkey alpha-subunit sequence demonstrated considerable identity with the horse (97% at the nucleotide level), confirming the very close evolutionary linkage between these two species. The predicted amino acid sequence revealed that the donkey alpha-subunit has the same unusual C-terminus as the horse alpha-subunit, when compared with all other mammalian alpha-subunits, including a Tyr-His transposition between positions 87 and 93 and Ile instead of Ser as the C-terminal residue. Since recent evidence indicates important involvement of this region of the alpha-subunit in receptor binding, these findings provide a possible partial explanation for the unique biological properties of the equine gonadotrophins.
采用逆转录聚合酶链反应（Reverse transcription-PCR）从垂体RNA中克隆驴（Equus asinus）糖蛋白激素α亚基转录本的编码区。驴α亚基序列与马的序列具有相当高的同源性（核苷酸水平为97%），证实了这两个物种之间非常紧密的进化联系。预测的氨基酸序列显示，与所有其他哺乳动物α亚基相比，驴α亚基与马α亚基具有相同的异常C末端，包括87和93位之间的酪氨酸-组氨酸换位以及C末端残基为异亮氨酸而非丝氨酸。由于最近的证据表明α亚基的这一区域在受体结合中起重要作用，这些发现为马促性腺激素独特的生物学特性提供了一个可能的部分解释。
