Wang Silu, Sokolowski Marla B
Department of Zoology, University of British Columbia, 6270 University Boulevard, Vancouver, British Columbia, CanadaV6T 1Z4.
Department of Ecology and Evolutionary Biology, University of Toronto, 25 Willcocks Street, Toronto, Ontario, CanadaM5S 3B2.
R Soc Open Sci. 2017 Apr 26;4(4):170042. doi: 10.1098/rsos.170042. eCollection 2017 Apr.
A pleiotropic gene governs multiple traits, which might constrain the evolution of complexity due to conflicting selection on these traits. However, if the pleiotropic effect is modular, then this can facilitate synergistic responses to selection on functionally related traits, thereby leveraging the evolution of complexity. To understand the evolutionary consequence of pleiotropy, the relation among functionally different traits governed by the same gene is key. We examined a pleiotropic function of the () gene with its rover and sitter allelic variants in fruit fly, . We measured 's effect on adult male aggressive behaviours and whether this effect was shaped by 's known role in food-related traits. Rover exhibited higher levels of offensive behaviour than sitters and s2, a sitter-like mutant on rover genetic background. With a Markov chain model, we estimated the rate of aggression escalation, and found that the rover pattern of aggressive escalation more rapidly intensified fights. Subsequent analysis revealed that this was not caused by 's effect on food-related traits, suggesting that might directly regulate aggressive behaviours. Food deprivation did not elevate aggression, but reduced intermediate-level aggressive behaviours. Aggression and other foraging-related behaviour might comprise a synergistic trait module underlaid by this pleiotropic gene.
一个多效基因控制多个性状，由于对这些性状的选择相互冲突，这可能会限制复杂性的进化。然而，如果多效性效应是模块化的，那么这可以促进对功能相关性状选择的协同反应，从而推动复杂性的进化。为了理解多效性的进化后果，由同一基因控制的功能不同性状之间的关系是关键。我们研究了果蝇中具有漫游者和静坐者等位基因变体的（）基因的多效性功能。我们测量了其对成年雄性攻击行为的影响，以及这种影响是否受其在与食物相关性状中的已知作用所塑造。漫游者比静坐者和s2（漫游者遗传背景下的类似静坐者的突变体）表现出更高水平的攻击行为。通过马尔可夫链模型，我们估计了攻击升级的速率，发现漫游者的攻击升级模式更迅速地加剧了争斗。随后的分析表明，这不是由其对与食物相关性状的影响引起的，这表明（该基因）可能直接调节攻击行为。食物剥夺并没有提高攻击性，而是减少了中等水平的攻击行为。攻击行为和其他与觅食相关的行为可能构成一个由这个多效基因支撑的协同性状模块。
