Rittschof C C, Robinson G E
Department of Entomology and Institute for Genomic Biology, University of Illinois Urbana-Champaign, Urban, IL, USA.
Genes Brain Behav. 2013 Nov;12(8):802-11. doi: 10.1111/gbb.12087. Epub 2013 Oct 9.
The social environment plays an essential role in shaping behavior for most animals. Social effects on behavior are often linked to changes in brain gene expression. In the honey bee (Apis mellifera L.), social modulation of individual aggression allows colonies to adjust the intensity with which they defend their hive in response to predation threat. Previous research has showed social effects on both aggression and aggression-related brain gene expression in honey bees, caused by alarm pheromone and unknown factors related to colony genotype. For example, some bees from less aggressive genetic stock reared in colonies with genetic predispositions toward increased aggression show both increased aggression and more aggressive-like brain gene expression profiles. We tested the hypothesis that exposure to a colony environment influenced by high levels of predation threat results in increased aggression and aggressive-like gene expression patterns in individual bees. We assessed gene expression using four marker genes. Experimentally induced predation threats modified behavior, but the effect was opposite of our predictions: disturbed colonies showed decreased aggression. Disturbed colonies also decreased foraging activity, suggesting that they did not habituate to threats; other explanations for this finding are discussed. Bees in disturbed colonies also showed changes in brain gene expression, some of which paralleled behavioral findings. These results show that bee aggression and associated molecular processes are subject to complex social influences.
对于大多数动物而言，社会环境在塑造行为方面起着至关重要的作用。社会对行为的影响通常与大脑基因表达的变化相关联。在蜜蜂（西方蜜蜂）中，个体攻击性的社会调节使蜂群能够根据捕食威胁调整其保卫蜂巢的强度。先前的研究表明，警报信息素以及与蜂群基因型相关的未知因素会对蜜蜂的攻击性和与攻击相关的大脑基因表达产生社会影响。例如，一些来自攻击性较弱遗传种群的蜜蜂，在具有攻击性增强遗传倾向的蜂群中饲养后，其攻击性和类似攻击性的大脑基因表达谱均会增加。我们检验了这样一个假设：暴露于受高水平捕食威胁影响的蜂群环境中，会导致个体蜜蜂的攻击性增加以及出现类似攻击性的基因表达模式。我们使用四个标记基因评估基因表达。实验诱导的捕食威胁改变了行为，但结果与我们的预测相反：受到干扰的蜂群攻击性降低。受到干扰的蜂群的觅食活动也减少了，这表明它们并未对威胁产生习惯化；本文还讨论了对此发现的其他解释。受到干扰的蜂群中的蜜蜂在大脑基因表达上也出现了变化，其中一些变化与行为结果相似。这些结果表明，蜜蜂的攻击性及相关分子过程受到复杂的社会影响。
