Key Laboratory of Zoological Systematics and Evolution, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
State Key Laboratory of Integrated Management of Pest Insects and Rodents, Institute of Zoology, Chinese Academy of Sciences, Beijing, China.
Genome Biol Evol. 2018 Dec 1;10(12):3230-3242. doi: 10.1093/gbe/evy250.
The Dmrt (doublesex and mab-3-related transcription factor) genes are transcription factors crucial for sex determination and sexual differentiation. In some social insects, doublesex (dsx) exhibits widespread caste-specific expression across different tissues and developmental stages and has been suggested as a candidate gene for regulating division of labor in social insects. We therefore conducted a molecular evolution analysis of the Dmrt gene family in 20 ants. We found that the insect-specific oligomerization domain of DSX, oligomerization domain 2, was absent in all ants, except for the two phylogenetically basal ant species (Ponerinae), whose social structure and organization resemble the presumed ancestral condition in ants. Phylogenetic reconstruction and selection analysis revealed that dsx evolved faster than the other three members of the Dmrt family. We found evidence for positive selection for dsx in the ant subfamilies with more advanced social organization (Myrmicinae and Formicinae), but not in the Ponerinae. Furthermore, we detected expression of two Dmrt genes, dsx and DMRT11E, in adult ants, and found a clear male-biased expression pattern of dsx in most species for which data are available. Interestingly, we did not detect male-biased expression of dsx in the two ant species that possess a genetic caste determination system. These results possibly suggest an association between the evolution of dsx and social organization as well as reproductive division of labor in ants.
DMRT(双倍性别和 mab-3 相关转录因子)基因是性别决定和性分化的关键转录因子。在一些社会性昆虫中,双倍性别(dsx)在不同组织和发育阶段表现出广泛的特定等级表达,并被认为是调节社会性昆虫分工的候选基因。因此,我们对 20 种蚂蚁中的 Dmrt 基因家族进行了分子进化分析。我们发现,除了两种系统发育上基础的蚂蚁物种(细腰亚科)外,所有蚂蚁的 DSX 昆虫特异性寡聚结构域,即寡聚结构域 2,均不存在,而这两种蚂蚁的社会结构和组织类似于蚂蚁的假定祖先状态。系统发育重建和选择分析表明,dsx 的进化速度比 Dmrt 家族的其他三个成员更快。我们发现,在具有更先进社会组织的蚂蚁亚科(Myrmicinae 和 Formicinae)中,dsx 存在正选择的证据,但在细腰亚科中则没有。此外,我们在成年蚂蚁中检测到了两个 Dmrt 基因,dsx 和 DMRT11E 的表达,并发现大多数有数据的物种中 dsx 存在明显的雄性偏性表达模式。有趣的是,我们在具有遗传等级决定系统的两种蚂蚁物种中没有检测到 dsx 的雄性偏性表达。这些结果可能表明,dsx 的进化与蚂蚁的社会组织以及生殖分工之间存在关联。