Krystek S R, Dias J A, Andersen T T
Biochemistry and Molecular Biology A-10, Albany Medical College, NY 12208.
Pept Res. 1992 May-Jun;5(3):165-8.
Using synthetic peptides, we previously identified portions of the lutropin alpha-subunit that are in contact with the beta-subunit. In order to elucidate structure/function differences of the glycoprotein hormones, a similar study was conducted for follitropin. Peptides corresponding to the follitropin alpha-subunit were synthesized using standard solid-phase procedures. Purified peptides were incubated in the presence of alpha- and beta-subunits of follitropin, and subunit recombination was monitored using gel permeation chromatography and reverse-phase high-pressure liquid chromatography. Peptide alpha 33-58, corresponding to a highly conserved portion of alpha-subunit, completely inhibited subunit recombination for 24 h, and allowed only partial (61%-71%) recombination after 48 h. Peptide alpha 51-65 or alpha 61-78 inhibited subunit recombination partially at 24 h, but almost full (greater than 80%) recombination was observed by 48 h. Peptides corresponding to the rest of the alpha-subunit, alpha 1-15, alpha 11-27, alpha 22-39, and alpha 73-92, did not inhibit recombination of the alpha- and beta-subunits. The data suggest that alpha-subunits have similar residues in contact with regions of the beta-subunits of both lutropin and follitropin, specifically involving residues from continuous regions of the alpha-subunit (residues 45-75). The data suggest that this region contains multiple sites of contact with the beta-subunit.
我们之前使用合成肽鉴定出了促黄体生成素α亚基中与β亚基接触的部分。为了阐明糖蛋白激素的结构/功能差异，我们对促卵泡生成素进行了类似的研究。使用标准固相方法合成了与促卵泡生成素α亚基对应的肽。将纯化后的肽在促卵泡生成素的α亚基和β亚基存在的情况下进行孵育，并使用凝胶渗透色谱法和反相高压液相色谱法监测亚基重组情况。与α亚基高度保守部分对应的肽α 33 - 58在24小时内完全抑制了亚基重组，48小时后仅允许部分（61% - 71%）重组。肽α 51 - 65或α 61 - 78在24小时时部分抑制了亚基重组，但到48小时时观察到几乎完全（大于80%）的重组。与α亚基其余部分对应的肽，α 1 - 15、α 11 - 27、α 22 - 39和α 73 - 92，并未抑制α亚基和β亚基的重组。数据表明，α亚基在与促黄体生成素和促卵泡生成素的β亚基区域接触时有相似的残基，特别是涉及α亚基连续区域（残基45 - 75）的残基。数据表明该区域包含与β亚基的多个接触位点。
