Hammoud S, Liu L, Carrell D T
Department of Surgery, University of Utah, Salt Lake City, 84108, USA.
Andrologia. 2009 Apr;41(2):88-94. doi: 10.1111/j.1439-0272.2008.00890.x.
Fertile males express two forms of sperm nuclear proteins, protamine 1 (P1) and protamine 2 (P2), in roughly equal quantities, whereas some infertile men have been shown to have a reduction in protamine content and an increase in the level of histones retained in mature sperm. In this study, we assessed histone and protamine levels in spermatozoa isolated from different layers of a density gradient centrifugation column to evaluate the nuclear protein content of the sperm population selected. Protamine levels were measured using acid gel electrophoresis and immunofluorescence, and the percentage of cells retaining histones was evaluated using aniline staining and immunofluorescence. Our data suggests that there is an inverse correlation between P1/P2 ratio and the level of histone expression in the different layers of the density gradient. Paradoxically, the 90% layer had a lower P1/P2 ratio, which corresponded with an increase in histone expression. It is concluded that although the sperm population selected in the 90% layer of the density gradient columns had a lower P1/P2 ratio, it was yet similar to the P1/P2 ratio observed in previously screened fertile donors.
可育男性会以大致相等的量表达两种形式的精子核蛋白，即鱼精蛋白1（P1）和鱼精蛋白2（P2），而一些不育男性已被证明鱼精蛋白含量降低，成熟精子中保留的组蛋白水平升高。在本研究中，我们评估了从密度梯度离心柱不同层分离出的精子中的组蛋白和鱼精蛋白水平，以评估所选精子群体的核蛋白含量。使用酸性凝胶电泳和免疫荧光测量鱼精蛋白水平，使用苯胺染色和免疫荧光评估保留组蛋白的细胞百分比。我们的数据表明，密度梯度不同层中的P1/P2比值与组蛋白表达水平呈负相关。矛盾的是，90%层的P1/P2比值较低，这与组蛋白表达增加相对应。得出的结论是，尽管在密度梯度柱90%层中选择的精子群体的P1/P2比值较低，但它与先前筛选的可育供体中观察到的P1/P2比值相似。
