Kocher Sarah D, Richard Freddie-Jeanne, Tarpy David R, Grozinger Christina M
Department of Genetics, North Carolina State University, Raleigh, NC, USA.
BMC Genomics. 2008 May 19;9:232. doi: 10.1186/1471-2164-9-232.
The molecular mechanisms underlying the post-mating behavioral and physiological transitions undergone by females have not been explored in great detail. Honey bees represent an excellent model system in which to address these questions because they exhibit a range of "mating states," with two extremes (virgins and egg-laying, mated queens) that differ dramatically in their behavior, pheromone profiles, and physiology. We used an incompletely-mated mating-state to understand the molecular processes that underlie the transition from a virgin to a mated, egg-laying queen. We used same-aged virgins, queens that mated once but did not initiate egg-laying, and queens that mated once and initiated egg-laying.
Differences in the behavior and physiology among groups correlated with the underlying variance observed in the top 50 predictive genes in the brains and the ovaries. These changes were correlated with either a behaviorally-associated pattern or a physiologically-associated pattern. Overall, these results suggest that the brains and the ovaries of queens are uncoupled or follow different timescales; the initiation of mating triggers immediate changes in the ovaries, while changes in the brain may require additional stimuli or take a longer time to complete. Comparison of our results to previous studies of post-mating changes in Drosophila melanogaster identified common biological processes affected by mating, including stress response and alternative-splicing pathways. Comparison with microarray data sets related to worker behavior revealed no obvious correlation between genes regulated by mating and genes regulated by behavior/physiology in workers.
Studying the underlying molecular mechanisms of post-mating changes in honey bee queens will not only give us insight into how molecular mechanisms regulate physiological and behavioral changes, but they may also lead to important insights into the evolution of social behavior. Post-mating changes in gene regulation in the brains and ovaries of honey bee queens appear to be triggered by different stimuli and may occur on different timescales, potentially allowing changes in the brains and the ovaries to be uncoupled.
雌性动物交配后行为和生理转变背后的分子机制尚未得到详细探究。蜜蜂是解决这些问题的绝佳模型系统，因为它们呈现出一系列“交配状态”，其中两个极端状态（未交配的处女蜂和已交配且产卵的蜂后）在行为、信息素谱和生理方面存在显著差异。我们利用一种不完全交配的交配状态来了解从处女蜂转变为已交配且产卵蜂后的分子过程。我们使用了同龄的处女蜂、交配一次但未开始产卵的蜂后以及交配一次并开始产卵的蜂后。
各组在行为和生理上的差异与大脑和卵巢中前50个预测基因所观察到的潜在差异相关。这些变化与行为相关模式或生理相关模式相关。总体而言，这些结果表明蜂后的大脑和卵巢是解耦的或遵循不同的时间尺度；交配的开始会立即触发卵巢的变化，而大脑的变化可能需要额外的刺激或更长时间才能完成。将我们的结果与先前关于黑腹果蝇交配后变化的研究进行比较，发现交配影响的常见生物学过程，包括应激反应和可变剪接途径。与与工蜂行为相关的微阵列数据集进行比较，发现交配调控的基因与工蜂行为/生理调控的基因之间没有明显相关性。
研究蜜蜂蜂后交配后变化的潜在分子机制不仅能让我们深入了解分子机制如何调节生理和行为变化，还可能为社会行为的进化带来重要见解。蜜蜂蜂后大脑和卵巢中交配后基因调控的变化似乎由不同刺激触发，可能发生在不同的时间尺度上，这可能使大脑和卵巢的变化解耦。
