The acetic acid-urea polyacrylamide gel electrophoresis system could separate very similar basic proteins on differences in size and effective charge. This system has been used for many years to analyse histones and their post-translational modifications and widely used in the study of mammal protamines. Two types of protamine have been described, the protamine 1 (P1) and the protamine 2 (P2) family members, which are synthetized by PRM1 and PRM2 genes. The ratio of P1 and P2 is important for predicting fertility in humans and mice. Therefore, the quantification of protamines is a fundamental step in order to establish the ratio between P1 and P2 in these species. In other mammals, studies linking sperm protamination and the protamine ratio with fertility are increasing. So, the use of an effective technique to separate and quantify protamines is important to study sperm P1/P2 ratio. Therefore, this article describes in detail a feasible and useful procedure to isolate bovine sperm protamines, to perform pre-electrophoresis with PEG solution and finally to carry out acid-urea polyacrylamide gel electrophoresis in reverse polarity. This technique allows a clear separation and efficient detection of bovine sperm protamines.

中文翻译：

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一种改进的醋酸-尿素聚丙烯酰胺电泳法评价牛精子鱼精蛋白

醋酸-尿素聚丙烯酰胺凝胶电泳系统可以分离大小和有效电荷不同的非常相似的碱性蛋白质。该系统多年来一直用于分析组蛋白及其翻译后修饰，并广泛用于哺乳动物鱼精蛋白的研究。已经描述了两种类型的鱼精蛋白，鱼精蛋白 1 (P1) 和鱼精蛋白 2 (P2) 家族成员，它们由 PRM1 和 PRM2 基因合成。P1 和 P2 的比率对于预测人类和小鼠的生育能力很重要。因此，鱼精蛋白的定量是确定这些物种中 P1 和 P2 之间比率的基本步骤。在其他哺乳动物中，将精子精蛋白和鱼精蛋白比率与生育能力联系起来的研究正在增加。所以，使用有效的技术来分离和量化鱼精蛋白对于研究精子 P1/P2 比率很重要。因此，本文详细介绍了一种可行且有用的分离牛精子鱼精蛋白，用PEG溶液进行预电泳，最后进行反极性酸-尿素聚丙烯酰胺凝胶电泳的方法。这种技术可以清楚地分离和有效检测牛精子鱼精蛋白。