Human Genetics Research Group, IDIBAPS, University of Barcelona, Casanova 143, 08036, Barcelona, Spain.
Adv Exp Med Biol. 2014;791:83-102. doi: 10.1007/978-1-4614-7783-9_6.
Protamines are the major nuclear proteins in sperm cells, having a crucial role in the correct packaging of the paternal DNA. The fact that protamine haploinsufficiency in mice resulted in abnormal chromatin packaging and male infertility suggested that the protamines could also be important candidates in explaining some of the idiopathic male infertility cases in humans. The first clinical studies focused on analyzing protamines at the protein level. Various studies have found the presence of an altered amount of protamines in some infertile patients, in contrast to the normal situation in fertile individuals where the two protamines, protamine 1 and protamine 2, are both present in approximately equal quantities. Subsequently, the protamine genes were the subject of various mutational genetic screening studies in search of variants that could be associated with deregulation in the protamine expression observed. The results of these protamine mutational studies showed that the presence of high penetrant mutations is a very rare cause of male infertility. However, some variants and some haplotypes described may behave as risk factors for male infertility. More recently, the presence of RNA in the mature sperm cell has also been investigated. The present chapter will introduce the basic aspects of protamine evolution and function and review the various articles published to date on the relationship between the protamines studied at the DNA, RNA, and protein levels and male infertility.
鱼精蛋白是精子细胞中的主要核蛋白，在正确包装父本 DNA 方面起着至关重要的作用。事实上，在老鼠中，鱼精蛋白单倍不足会导致染色质包装异常和雄性不育，这表明鱼精蛋白也可能是解释人类一些特发性男性不育病例的重要候选因素。最初的临床研究集中在分析蛋白质水平的鱼精蛋白。各种研究发现，一些不育患者的鱼精蛋白数量发生了改变，而在生育能力正常的个体中，两种鱼精蛋白，即鱼精蛋白 1 和鱼精蛋白 2，的含量大致相等。随后，鱼精蛋白基因成为各种突变遗传筛选研究的主题，以寻找可能与观察到的鱼精蛋白表达失调相关的变体。这些鱼精蛋白突变研究的结果表明，高外显率突变的存在是男性不育症的一个非常罕见的原因。然而，一些描述的变体和单倍型可能表现为男性不育的风险因素。最近，成熟精子细胞中 RNA 的存在也得到了研究。本章将介绍鱼精蛋白进化和功能的基本方面，并回顾迄今为止关于在 DNA、RNA 和蛋白质水平上研究的鱼精蛋白与男性不育之间关系的各种文章。
