Caste differentiation happens early in development to produce gynes as future colony germlines and workers as present colony soma. However, gynes need insemination to become functional queens, a transition that initiates reproductive role differentiation relative to unmated gynes. Here, we analyze the anatomy and transcriptomes of brains during this differentiation process within the reproductive caste of Monomorium pharaonis. Insemination terminated brain growth, whereas unmated control gynes continued to increase brain volume. Transcriptomes revealed a specific gene regulatory network (GRN) mediating both brain anatomy changes and behavioral modifications. This reproductive role differentiation GRN hardly overlapped with the gyne-worker caste differentiation GRN, but appears to be also used by distantly related ants where workers became germline individuals after the queen caste was entirely or partially lost. The genes corazonin and neuroparsin A in the anterior neurosecretory cells were overexpressed in individuals with reduced or nonreproductive roles across all four ant species investigated.

种姓分化发生在发育的早期，以产生作为未来群体生殖系的雌性和作为当前群体体细胞的工人。然而，女性需要授精才能成为功能性皇后，这是一种相对于未交配的女性而言引发生殖角色分化的转变。在这里，我们分析了在Monomorium pharaonis生殖种姓的这种分化过程中大脑的解剖结构和转录组. 授精终止了大脑的生长，而未交配的对照女性继续增加脑容量。转录组揭示了一个特定的基因调控网络 (GRN) 介导大脑解剖结构的变化和行为的改变。这种生殖角色分化 GRN 几乎不与女工种姓分化 GRN 重叠，但似乎也被远亲蚂蚁使用，在这些蚂蚁完全或部分丧失女王种姓后，工蚁成为种系个体。在研究的所有四种蚂蚁物种中，前神经分泌细胞中的corazonin和neuroparsin A基因在具有降低或非生殖作用的个体中过度表达。