Sairam M R, Li C H
Int J Pept Protein Res. 1979 Apr;13(4):394-402.
The alpha and beta subunits of human follitropin were isolated in a high state of purity. The tryptophan fluorescence of the native hormone and the isolated beta subunit are different. The N-terminus of the alpha and beta subunits was identified as valine and aspartic acid respectively. While recombination of the isolated alpha and beta subunits restores the electrophoretic mobility of the intact hormone, its receptor binding activity cannot be fully regenerated. Substitution of the human follitropin alpha by an ovine lutropin alpha subunit, to form a recombinant with the follitropin beta subunit, generates a complex with 2-3 receptor binding activity of the native human follitropin and the same activity as ovine follitropin. Acylation of the intact hormone does not disrupt the quaternary structure but leads to complete inactivation. Acylation studies with the subunits suggests the crucial role of the epsilon-amino groups of the alpha subunit in determining biological activity.
人促卵泡激素的α亚基和β亚基以高纯度状态分离出来。天然激素和分离出的β亚基的色氨酸荧光不同。α亚基和β亚基的N端分别被鉴定为缬氨酸和天冬氨酸。虽然分离出的α亚基和β亚基重组可恢复完整激素的电泳迁移率，但其受体结合活性无法完全再生。用人促卵泡激素α亚基替换为羊促黄体激素α亚基，与促卵泡激素β亚基形成重组体，产生的复合物具有天然人促卵泡激素2 - 3倍的受体结合活性，且与羊促卵泡激素活性相同。完整激素的酰化不会破坏四级结构，但会导致完全失活。亚基的酰化研究表明α亚基的ε-氨基在决定生物活性方面起关键作用。
