Ingram Krista K, Oefner Peter, Gordon Deborah M
Department of Biological Sciences, 371 Serra Mall, Stanford University, Stanford, CA 94305, USA.
Mol Ecol. 2005 Mar;14(3):813-8. doi: 10.1111/j.1365-294X.2005.02450.x.
In social insects, groups of workers perform various tasks such as brood care and foraging. Transitions in workers from one task to another are important in the organization and ecological success of colonies. Regulation of genetic pathways can lead to plasticity in social insect task behaviour. The colony organization of advanced eusocial insects evolved independently in ants, bees, and wasps and it is not known whether the genetic mechanisms that influence behavioural plasticity are conserved across species. Here we show that a gene associated with foraging behaviour is conserved across social insect species, but the expression patterns of this gene are not. We cloned the red harvester ant (Pogonomyrmex barbatus) ortholog (Pbfor) to foraging, one of few genes implicated in social organization, and found that foraging behaviour in harvester ants is associated with the expression of this gene; young (callow) worker brains have significantly higher levels of Pbfor mRNA than foragers. Levels of Pbfor mRNA in other worker task groups vary among harvester ant colonies. However, foragers always have the lowest expression levels compared to other task groups. The association between foraging behaviour and the foraging gene is conserved across social insects but ants and bees have an inverse relationship between foraging expression and behaviour.
在社会性昆虫中，工蚁群体执行各种任务，如照料幼虫和觅食。工蚁从一项任务转换到另一项任务，这对蚁群的组织和生态成功至关重要。遗传途径的调控可导致社会性昆虫任务行为的可塑性。高等真社会性昆虫的蚁群组织在蚂蚁、蜜蜂和黄蜂中独立进化，目前尚不清楚影响行为可塑性的遗传机制是否在物种间保守。在这里，我们表明与觅食行为相关的一个基因在社会性昆虫物种间是保守的，但该基因的表达模式并非如此。我们克隆了红色收获蚁（Pogonomyrmex barbatus）与觅食相关的直系同源基因（Pbfor），这是少数与社会组织有关的基因之一，发现收获蚁的觅食行为与该基因的表达有关；年轻（刚羽化）工蚁大脑中的Pbfor mRNA水平显著高于觅食工蚁。其他工蚁任务群体中的Pbfor mRNA水平在不同的收获蚁蚁群中有所不同。然而，与其他任务群体相比，觅食工蚁的表达水平总是最低。觅食行为与觅食基因之间的关联在社会性昆虫中是保守的，但蚂蚁和蜜蜂在觅食表达与行为之间存在相反的关系。
