Tex10 in day2 embryonic bodies (EBs). Tex10 in day2 embryonic bodies (EBs)

Testis-specific transcript 10 (Tex10) is highly expressed in the testis, embryonic stem cells (ESCs), and primordial germ cells (PGCs). We previously generated a Tex10 knockout mouse model demonstrating its critical roles in ESC pluripotency and preimplantation development. Here, using conditional knockout mice and dTAG-degron ESCs, we show Tex10 is required for spermatogenesis and ESC-to-PGCLC differentiation. Specifically, Tex10-null spermatocytes arrest at metaphase I, compromising round spermatid formation. Tex10 depletion and overexpression compromise and enhance ESC-to-PGCLC differentiation, respectively. Mechanistically, bulk and single-cell RNA sequencing reveals that Tex10 depletion downregulates genes involved in pluripotency, PGC development, and spermatogenesis while upregulating genes promoting somatic programs. Chromatin occupancy study reveals that Tex10 binds to H3K4me3-marked promoters of Psmd3 and Psmd7, negative regulators of Wnt signaling, and activates their expression, thereby restraining Wnt signaling. Our study identifies Tex10 as a previously unappreciated factor in spermatogenesis and PGC development, offering potential therapeutic insights for treating male infertility. Overall design: Embryonic bodies (EBs) were treated with DMSO or dTAG13 for two days and dissociated with 0.05% Trypsin-EDTA to generate single-cell suspension for single-cell sequencing.睾丸特异性转录本10（Tex10）在睾丸、胚胎干细胞（ESCs）以及原始生殖细胞（PGCs）中高表达。我们此前构建了Tex10基因敲除小鼠模型，证实其在ESC多能性维持及着床前胚胎发育过程中发挥关键作用。本研究借助条件性基因敲除小鼠与dTAG-degron胚胎干细胞，证实Tex10对于精子发生以及ESC向类原始生殖细胞（PGCLC）的分化不可或缺。具体而言，Tex10基因敲除的精母细胞会停滞于减数分裂I中期，进而阻碍圆形精子细胞的生成。Tex10的敲低与过表达分别会削弱与增强ESC向PGCLC的分化能力。机制层面，批量RNA测序（bulk RNA sequencing）与单细胞RNA测序（single-cell RNA sequencing）结果显示，Tex10敲低会下调参与多能性维持、PGC发育及精子发生的基因表达，同时上调促进体细胞程序的基因表达。染色质占据实验（chromatin occupancy study）证实，Tex10可结合Wnt信号通路负调控因子Psmd3与Psmd7的H3K4me3修饰启动子区域，并激活二者的转录，从而抑制Wnt信号通路的激活。本研究证实Tex10是此前未被发现的精子发生与PGC发育调控因子，为男性不育的治疗提供了潜在的理论依据与治疗靶点。实验整体设计：将胚胎体（EBs）用二甲基亚砜（DMSO）或dTAG13处理两天，随后以0.05%胰蛋白酶-EDTA消化制备单细胞悬液，用于后续单细胞测序。