Lee Hong Jo, Han Jeong Hoon, Chapman Brittany, Jung Kyung Min, Rudd Isabella, Han Jae Yong, Kim Tae Hyun
Department of Animal Science, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802, USA; Division of Animal Sciences, University of Missouri, Columbia, MO, USA.
Department of Animal Science, Huck Institutes of the Life Sciences, Pennsylvania State University, University Park, PA 16802, USA.
Poult Sci. 2025 Apr;104(4):104932. doi: 10.1016/j.psj.2025.104932. Epub 2025 Feb 20.
Asymmetrical gonadal development is an intriguing phenomenon observed in the majority of female birds. In chickens, the left gonad of female embryos develops into a functional ovary, while the right gonad undergoes degeneration during embryogenesis. This sexually dimorphic trait is primarily induced by the spatial differential expression of the paired like homeodomain 2 (PITX2) gene. However, a comprehensive understanding of the transcriptional profile of the developing gonads during asymmetric development is still lacking. To elucidate the molecular mechanism of asymmetric gonadal development in chickens, we compared the transcriptomes between left and right gonads of female chickens using bulk- and single cell-RNA sequencing (scRNA-seq) approaches. Our bulk RNA-seq analysis of the female chicken gonads at E5 (HH26), E6.5 (HH30), E8 (HH34), and E9.5 (HH36) revealed significant differential gene expression between the left and right female chicken gonads, particularly in signaling pathways, cell cycle, and metabolic processes. Moreover, scRNA-seq analysis revealed that coelomic epithelial, interstitial, and pre-granulosa cells of the left gonads at E5 show a highly proliferative status compared to the right gonad, contributing to the asymmetric gonadal cell proliferation, which may be regulated by the transforming growth factor beta (TGFβ) signaling pathway. Our findings demonstrate that dynamic cell-type-specific transcriptional profiles during embryogenesis play a vital role in the asymmetric gonadal development of female chickens.
不对称性腺发育是在大多数雌性鸟类中观察到的一种有趣现象。在鸡中，雌性胚胎的左侧性腺发育成功能性卵巢，而右侧性腺在胚胎发生过程中发生退化。这种性别二态性特征主要由配对样同源结构域2（PITX2）基因的空间差异表达诱导。然而，目前仍缺乏对不对称发育过程中发育性腺转录谱的全面了解。为了阐明鸡不对称性腺发育的分子机制，我们使用批量和单细胞RNA测序（scRNA-seq）方法比较了雌性鸡左右性腺的转录组。我们对E5（HH26）、E6.5（HH30）、E8（HH34）和E9.5（HH36）的雌性鸡性腺进行的批量RNA-seq分析显示，雌性鸡左右性腺之间存在显著的差异基因表达，特别是在信号通路、细胞周期和代谢过程中。此外，scRNA-seq分析显示，与右侧性腺相比，E5时左侧性腺的体腔上皮细胞、间质细胞和前颗粒细胞显示出高度增殖状态，这有助于性腺细胞的不对称增殖，这可能受转化生长因子β（TGFβ）信号通路调控。我们的研究结果表明，胚胎发生过程中动态的细胞类型特异性转录谱在雌性鸡不对称性腺发育中起着至关重要的作用。
