Data from: Effect of the early social environment on behavioural and genomic responses to a social challenge in a cooperatively breeding vertebrate

The early social environment can have substantial, lifelong effects on vertebrate social behaviour, which can be mediated by developmental plasticity of brain gene expression. Early life effects can influence immediate behavioural responses towards later-life social challenges and can activate different gene expression responses. However, while genomic responses to social challenges have been reported frequently, how developmental experience influences the shape of these genomic reaction norms remains largely unexplored. We tested how manipulating the early social environment of juvenile, cooperatively-breeding cichlids, Neolamprologus pulcher, affects their behavioural and brain genomic responses when competing over a resource. Juveniles were reared either with or without a breeder pair and a helper. Fish reared with family members behaved more appropriately in the competition than when reared without. We investigated whether the different social rearing environments also affected the genomic responses to the social challenge. A set of candidate genes, coding for hormones and receptors influencing social behaviour, were measured in the telencephalon and hypothalamus. Social environment and social challenge both influenced gene expression of egr-1 (early growth response 1) and gr1 (glucocorticoid receptor 1) in the telencephalon and of bdnf (brain derived neurotrophic factor) in the hypothalamus. A global analysis of the 11 expression patterns in the two brain areas showed that neurogenomic states diverged more strongly between intruder fish and control fish when they had been reared in a natural social setting. Our results show that same molecular pathways may be used differently in response to a social challenge depending on early life experiences.早期社会环境可对脊椎动物的社会行为产生持久且显著的影响，此类影响可通过大脑基因表达的发育可塑性（developmental plasticity）介导实现。生命早期的社会经历可影响个体应对后续生命阶段社会挑战时的即时行为反应，并能激活不同的基因表达应答模式。然而，尽管学界已频繁报道了针对社会挑战的基因组应答，但发育经历如何调控这些基因组反应规范（genomic reaction norms）的特征，目前仍未得到充分探索。我们通过操控幼年期合作繁殖慈鲷（Neolamprologus pulcher）的早期社会环境，探究其在资源竞争过程中的行为与大脑基因组应答变化。实验幼鱼被分为两种饲养条件：一组伴随繁殖亲代对与协助者饲养，另一组则无此类社会环境。相较于无家庭环境饲养的幼鱼，有家庭成员陪伴饲养的个体在资源竞争中表现出更恰当的行为模式。我们进一步探究了不同的早期社会饲养环境，是否会影响个体针对社会挑战的基因组应答。我们对端脑（telencephalon）与下丘脑（hypothalamus）中编码影响社会行为的激素与受体的一组候选基因进行了表达量检测。社会饲养环境与社会挑战均会影响端脑内egr-1（early growth response 1，早期生长应答基因1）与gr1（glucocorticoid receptor 1，糖皮质激素受体1）的基因表达，以及下丘脑内bdnf（brain derived neurotrophic factor，脑源性神经营养因子）的基因表达。对两个脑区的11种表达模式进行的全局分析显示：当幼鱼在自然社会环境中饲养时，入侵鱼与对照组鱼之间的神经基因组状态差异更为显著。本研究结果表明，针对社会挑战的相同分子通路，其激活模式可能因个体生命早期的经历而存在差异。