Intronic nature of the rat luteinizing hormone receptor gene defines a soluble receptor subspecies with hormone binding activity.
Intronic nature of the rat luteinizing hormone receptor gene defines a soluble receptor subspecies with hormone binding activity.
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大鼠黄体生成激素受体基因的内含子性质定义了具有激素结合活性的可溶性受体亚种。
DOI：
10.1016/s0021-9258(17)45380-4
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发表时间：
1990
期刊：
影响因子：
--
通讯作者：
M. Dufau
中科院分区：
文献类型：
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作者：
C. Tsai‐Morris;E. Buczko;Wei Wang;M. Dufau
用大鼠卵巢LH受体cDNA探针克隆了一个大鼠睾丸LH受体cDNA，该cDNA含有266个碱基对的缺失，导致第一跨膜区缺失和开放阅读框截短。该克隆与LH受体基因组DNA的限制性片段的比较揭示了在内含子受体剪接位点和下一个外显子内存在的共有序列TTXCAG之后的潜在可变剪接位点，解释了在该cDNA中观察到的特异性缺失突变。睾丸cDNA在COS1细胞中的表达导致合成和分泌对LH和人绒毛膜促性腺激素具有高亲和力和特异性的可溶性结合蛋白。这些研究表明，LH受体基因在编码分子细胞外结构域的区域内包含内含子，这决定了LH受体亚型的性质和产生。LH受体可溶性形式的表达表明氨基末端胞外区在促性腺激素结合中起主要作用。LH受体的这些特征与大多数其他G蛋白偶联受体不同，这些G蛋白偶联受体是无内含子的，并且在跨膜区而不是胞外结构域中含有其结合位点。
A rat testicular luteinizing hormone (LH) receptor cDNA containing a 266-base pair deletion resulting in the omission of the 1st transmembrane region and truncation of the open reading frame was isolated using a rat ovarian LH receptor cDNA probe. Comparison of this clone with a restriction fragment from the LH receptor genomic DNA revealed potential alternative splice sites following the consensus sequence TTXCAG that is present at an intron acceptor splice site and also within the next exon, accounting for the specific deletion mutation observed in this cDNA. Expression of the testicular cDNA in COS1 cells resulted in synthesis and secretion of a soluble binding protein with high affinity and specificity for LH and human chorionic gonadotropin. These studies have demonstrated that the LH receptor gene contains intron(s) within the region coding for the extracellular domain of the molecule, which determine the nature and generation of LH receptor isoforms. Expression of the soluble form of the LH receptor has indicated that the amino-terminal extracellular region plays a major role in gonadotropin binding. These features of the LH receptor are distinct from those of most other G protein-coupled receptors, which are intronless and contain their binding sites within the transmembrane region rather than the extracellular domain.