Saleh Ziabari Omid, Zhong Qingyi, Purandare Swapna R, Reiter Joel, Zera Anthony J, Brisson Jennifer A
Department of Biology, University of Rochester, Rochester, NY 14610, USA.
Current address: Department of Computational Biology, Indraprastha Institute of Information Technology Delhi; New Delhi, India.
Curr Res Insect Sci. 2022 May 21;2:100039. doi: 10.1016/j.cris.2022.100039. eCollection 2022.
Alternative, intraspecific phenotypes offer an opportunity to identify the mechanistic basis of differences associated with distinctive life history strategies. Wing dimorphic insects, in which both flight-capable and flight-incapable individuals occur in the same population, are particularly well-studied in terms of why and how the morphs trade off flight for reproduction. Yet despite a wealth of studies examining the differences between female morphs, little is known about male differences, which could arise from different causes than those acting on females. Here we examined reproductive, gene expression, and biochemical differences between pea aphid () winged and wingless males. We find that winged males are competitively superior in one-on-one mating circumstances, but wingless males reach reproductive maturity faster and have larger testes. We suggest that males tradeoff increased local matings with concurrent possible inbreeding for outbreeding and increased ability to find mates. At the mechanistic level, differential gene expression between the morphs revealed a possible role for activin and insulin signaling in morph differences; it also highlighted genes not previously identified as being functionally important in wing polymorphism, such as genes likely involved in sperm production. Further, we find that winged males have higher lipid levels, consistent with their use as flight fuel, but we find no consistent patterns of different levels of activity among five enzymes associated with lipid biosynthesis. Overall, our analyses provide evidence that winged versus wingless males exhibit differences at the reproductive, gene expression, and biochemical levels, expanding the field's understanding of the functional aspects of morph differences.
另一种情况是，种内表型为识别与独特生活史策略相关的差异的机制基础提供了机会。在翅二型昆虫中，有飞行能力和无飞行能力的个体出现在同一群体中，就形态如何以及为何在飞行和繁殖之间进行权衡这方面，人们已经进行了深入研究。然而，尽管有大量研究探讨了雌性形态之间的差异，但对于雄性差异却知之甚少，雄性差异可能由与作用于雌性的原因不同的其他原因引起。在这里，我们研究了豌豆蚜有翅和无翅雄性之间的生殖、基因表达和生化差异。我们发现，有翅雄性在一对一交配情况下具有竞争优势，但无翅雄性达到生殖成熟的速度更快且睾丸更大。我们认为，雄性在增加本地交配机会与同时可能的近亲繁殖之间进行权衡，以实现远交和提高寻找配偶的能力。在机制层面，形态之间的差异基因表达揭示了激活素和胰岛素信号传导在形态差异中可能发挥的作用；它还突出了一些以前未被确定在翅多态性中具有功能重要性的基因，例如可能参与精子产生的基因。此外，我们发现有翅雄性的脂质水平较高，这与它们用作飞行燃料一致，但我们在与脂质生物合成相关的五种酶中没有发现不同活性水平的一致模式。总体而言，我们的分析提供了证据，表明有翅和无翅雄性在生殖、基因表达和生化水平上存在差异，扩展了该领域对形态差异功能方面的理解。
