Sexes suffer from suboptimal lifespan because of genetic conflict in a seed beetle
Sexes suffer from suboptimal lifespan because of genetic conflict in a seed beetle
复制标题
DOI：
10.1098/rspb.2012.1345
复制
发表时间：
2012-10-22
影响因子：
4.7
通讯作者：
Maklakov, Alexei A.
中科院分区：
文献类型：
--
作者：
Berg, Elena C.;Maklakov, Alexei A.
雄性和雌性有不同的成功繁殖途径，导致了性别在寿命和生殖努力的年龄分配上的差异。目前和未来繁殖之间的权衡通常由雄性和雌性以不同的方式解决，由于局灶内的性别冲突，两性在达到其特定性别的最佳状态的能力方面可能受到限制。这种基因对抗可能对进化有深远的影响，但它在衰老和寿命方面的作用仍未解决。我们提供了直接的实验证据，证明为了最大限度地提高斑纹豆象种子甲虫的相对适合度，雄性活得更长，雌性活得更短。通过在遗传异质性的种群中进行人工选择，我们创造了复制的长寿命系，其中雄性平均寿命比短寿命系长27%。正如理论预测的那样，随后的分析表明，与向下选择相比，对男性寿命的向上选择降低了相对男性的适合度，但提高了相对女性的适合度。因此，我们证明了延长寿命的基因可以帮助一种性别，同时伤害另一种性别。我们的结果表明，性别对立限制了适应性的生活史进化，支持了一种在一生中保持基因变异的新方法，并主张将性别效应更好地整合到旨在延长寿命的应用研究计划中。
Males and females have different routes to successful reproduction, resulting in sex differences in lifespan and age-specific allocation of reproductive effort. The trade-off between current and future reproduction is often resolved differently by males and females, and both sexes can be constrained in their ability to reach their sex-specific optima owing to intralocus sexual conflict. Such genetic antagonism may have profound implications for evolution, but its role in ageing and lifespan remains unresolved. We provide direct experimental evidence that males live longer and females live shorter than necessary to maximize their relative fitness in Callosobruchus maculatus seed beetles. Using artificial selection in a genetically heterogeneous population, we created replicate long-life lines where males lived on average 27 per cent longer than in short-life lines. As predicted by theory, subsequent assays revealed that upward selection on male lifespan decreased relative male fitness but increased relative female fitness compared with downward selection. Thus, we demonstrate that lifespan-extending genes can help one sex while harming the other. Our results show that sexual antagonism constrains adaptive life-history evolution, support a novel way of maintaining genetic variation for lifespan and argue for better integration of sex effects into applied research programmes aimed at lifespan extension.