We sequenced more than 52,500 single cells from embryonic day 11.5 (E11.5) postembryonic day 5 (P5) gonads and performed lineage tracing to analyze primordial follicles and wave 1 medullar follicles during mouse fetal and perinatal oogenesis. Germ cells clustered into six meiotic substages, as well as dying/nurse cells. Wnt-expressing bipotential precursors already present at E11.5 are followed at each developmental stage by two groups of ovarian pregranulosa (PG) cells. One PG group, bipotential pregranulosa (BPG) cells, derives directly from bipotential precursors, expresses Foxl2 early, and associates with cysts throughout the ovary by E12.5. A second PG group, epithelial pregranulosa (EPG) cells, arises in the ovarian surface epithelium, ingresses cortically by E12.5 or earlier, expresses Lgr5, but delays robust Foxl2 expression until after birth. By E19.5, EPG cells predominate in the cortex and differentiate into granulosa cells of quiescent primordial follicles. In contrast, medullar BPG cells differentiate along a distinct pathway to become wave 1 granulosa cells. Reflecting their separate somatic cellular lineages, second wave follicles were ablated by diptheria toxin treatment of Lgr5-DTR-EGFP mice at E16.5 while first wave follicles developed normally and supported fertility. These studies provide insights into ovarian somatic cells and a resource to study the development, physiology, and evolutionary conservation of mammalian ovarian follicles.

我们从胚胎第11.5天（E11.5）胚胎后第5天（P5）生殖腺开始对52,500多个单细胞进行了测序，并进行了谱系追踪分析，以分析小鼠胎儿和围产期卵生过程中的原始卵泡和第1波髓泡。生殖细胞和垂死/哺乳细胞聚集成六个减数分裂亚阶段。在每个发育阶段，已经存在于E11.5的表达Wnt的双能前体被两组卵巢前颗粒（PG）细胞跟踪。一个PG组，即双势前颗粒（BPG）细胞，直接来自双势前体，早期表达Foxl2，并通过E12.5与整个卵巢的囊肿相关。第二个PG组，即上皮前颗粒（EPG）细胞，出现在卵巢表面上皮中，通过E12.5或更早的皮质进入，表达Lgr5，但将健壮的Foxl2表达延迟到出生后。通过E19.5，EPG细胞在皮质中占主导地位，并分化为静止的原始原始卵泡的颗粒细胞。相反，髓样BPG细胞沿独特的途径分化成为1波颗粒细胞。反映它们各自的体细胞谱系，第二波卵泡在E16.5通过白喉毒素处理对Lgr5-DTR-EGFP小鼠进行消融，而第一波卵泡正常发育并支持生育。这些研究提供了对卵巢体细胞的见解，并为研究哺乳动物卵巢卵泡的发育，生理学和进化保存提供了资源。髓样BPG细胞沿着独特的途径分化，成为第1波颗粒细胞。反映它们各自的体细胞谱系，第二波卵泡在E16.5通过白喉毒素处理对Lgr5-DTR-EGFP小鼠进行消融，而第一波卵泡正常发育并支持生育。这些研究提供了对卵巢体细胞的见解，并为研究哺乳动物卵巢卵泡的发育，生理学和进化保存提供了资源。髓样BPG细胞沿着独特的途径分化，成为第1波颗粒细胞。反映它们各自的体细胞谱系，第二波卵泡在E16.5通过白喉毒素处理对Lgr5-DTR-EGFP小鼠进行消融，而第一波卵泡正常发育并支持生育。这些研究提供了对卵巢体细胞的见解，并为研究哺乳动物卵巢卵泡的发育，生理学和进化保存提供了资源。