Department of Environmental and Biological Sciences, University of Eastern Finland, Joensuu, Finland.
Natural Resources Institute Finland (Luke), Joensuu, Finland.
J Evol Biol. 2020 May;33(5):584-594. doi: 10.1111/jeb.13592. Epub 2020 Feb 7.
In a large majority of animal species, the only contribution of males to the next generation has been assumed to be their genes (sperm). However, along with sperm, seminal plasma contains a wide array of extracellular factors that have many important functions in reproduction. Yet, the potential intergenerational effects of these factors are virtually unknown. We investigated these effects in European whitefish (Coregonus lavaretus) by experimentally manipulating the presence and identity of seminal plasma and by fertilizing the eggs of multiple females with the manipulated and unmanipulated semen of several males in a full-factorial breeding design. The presence of both own seminal plasma and foreign seminal plasma inhibited sperm motility, and the removal of own seminal plasma decreased embryo survival. Embryos hatched significantly earlier after both semen manipulations than in control fertilizations; foreign seminal plasma also increased offspring aerobic swimming performance. Given that our experimental design allowed us to control potentially confounding sperm-mediated (sire) effects and maternal effects, our results indicate that seminal plasma may have direct intergenerational consequences for offspring phenotype and performance. This novel source of offspring phenotypic variance may provide new insights into the evolution of polyandry and mechanisms that maintain heritable variation in fitness and associated female mating preferences.
在大多数动物物种中，雄性对下一代的唯一贡献被认为是他们的基因（精子）。然而，除了精子，精液还包含一系列广泛的细胞外因子，这些因子在生殖中具有许多重要的功能。然而，这些因素的潜在代际效应实际上是未知的。我们通过实验操纵精液中精液和外源精液的存在和身份，并在完全因子设计中用多个雄性的处理和未处理的精液使多个雌性的卵子受精，从而在欧洲白鱼（Coregonus lavaretus）中研究了这些效应。自身精液和外源精液的存在均抑制精子运动能力，而自身精液的去除则降低了胚胎存活率。与对照受精相比，两种精液处理后胚胎孵化明显更早；外源精液还提高了后代的有氧游泳能力。鉴于我们的实验设计能够控制潜在的混杂精子介导的（父本）效应和母体效应，我们的结果表明，精液可能对后代表型和表现直接产生代际影响。这种后代表型变异的新来源可能为多配偶制的进化以及维持适应性和相关雌性交配偏好的遗传变异的机制提供新的见解。
