Abstract：
Avian ovaries develop asymmetrically apart from prey birds, with only the left ovary growing more towards functional organs. Here, we analyze over 135,000 cells from chick\'s left and right ovaries at six distinct embryonic developmental stages utilizing single-cell transcriptome sequencing. We delineate gene expression patterns across 15 cell types within these embryo ovaries, revealing side-specific development. The left ovaries exhibit cortex cells, zygotene germ cells, and transcriptional changes unique to the left side. Differential gene expression analysis further identifies specific markers and pathways active in these cell types, highlighting the asymmetry in ovarian development. A fine-scale analysis of the germ cell meiotic transcriptome reveals seven distinct clusters with gene expression patterns specific to various meiotic stages. The study also identifies signaling pathways and intercellular communications, particularly between pre-granulosa and germ cells. Spatial transcriptome analysis shows the asymmetry, demonstrating cortex cells exclusively in the left ovary, modulating neighboring cell types through putative secreted signaling molecules. Overall, this single-cell analysis provides insights into the molecular mechanisms of the asymmetric development of avian ovaries, particularly the significant role of cortex cells in the left ovary.
摘要：
鸟类卵巢与猎物鸟类不对称发育，只有左卵巢向功能器官生长。这里,我们分析了超过135,000个细胞从鸡的左和右卵巢在六个不同的胚胎发育阶段，利用单细胞转录组测序。我们描绘了这些胚胎卵巢中15种细胞类型的基因表达模式，揭示特定侧面的发展。左卵巢表现出皮质细胞，受精卵生殖细胞,和左侧特有的转录变化。差异基因表达分析进一步确定了在这些细胞类型中活跃的特定标记和途径。突出卵巢发育的不对称性。对生殖细胞减数分裂转录组的精细分析揭示了七个不同的簇，其基因表达模式对各个减数分裂阶段具有特异性。该研究还确定了信号通路和细胞间通讯，特别是在前颗粒细胞和生殖细胞之间。空间转录组分析显示了不对称性，仅在左卵巢显示皮质细胞，通过推定的分泌信号分子调节相邻细胞类型。总的来说,这种单细胞分析提供了对禽类卵巢不对称发育的分子机制的见解，特别是皮质细胞在左卵巢中的重要作用。
