Extensive studies have shown that estrogenic endocrine-disrupting chemicals (EDCs) can disrupt testis differentiation and even cause feminization in vertebrates. However, little is known about the mechanisms by which estrogenic EDCs disrupt testis differentiation. Here, we employed Xenopus laevis, a model amphibian species sensitive to estrogenic EDCs, to explore the molecular and cellular events by which 17β-estradiol (E2) disrupts testis differentiation and causes feminization. Following waterborne exposure to E2 from stage 45/46, genetically male X. laevis were confirmed to undergo testis differentiation inhibition and ovary differentiation activation at stages 52 and 53, ultimately displaying gonadal feminization at stage 66. Using a time-course RNA sequencing approach, we then identified thousands of differentially expressed transcripts (DETs) in genetically male gonad-mesonephros complexes at stages 48, 50 and 52 (the window for testis differentiation) between E2 treatment and the control. Enrichment analysis suggests alterations in cell proliferation, extracellular matrix, and cell motility following E2 exposure. Further verification by multiple methods demonstrated that E2 inhibited cell proliferation, disrupted extracellular matrix, and altered cell motility in the genetically male gonads compared with controls, implying that these events together contributed to testis differentiation disruptions and feminization in X. laevis. This study for the first time uncovered some of the early molecular and cellular events by which estrogen disrupts testicular differentiation and causes feminization in X. laevis. These new findings improve our understanding of the mechanisms by which estrogenic EDCs disrupt testicular differentiation in vertebrates.

大量研究表明，破坏雌激素的化学物质（EDC）可以破坏睾丸的分化，甚至导致脊椎动物女性化。然而，关于雌激素EDC破坏睾丸分化的机制知之甚少。在这里，我们使用非洲爪蟾，模型两栖动物到雌激素内分泌干扰物敏感，探索的分子和细胞事件，通过该17 β雌二醇（E2）破坏睾丸分化并引起女性化。在水性暴露于45/46期的E2之后，遗传上是男性X. laevis被证实在第52和53阶段经历了睾丸分化抑制和卵巢分化激活，最终在第66阶段表现出性腺女性化。使用时程RNA测序方法，我们随后在遗传上的男性性腺中鉴定了成千上万个差异表达的转录本（DET）。在E2治疗和对照之间处于第48、50和52期（睾丸分化的窗口）的中肾复合体。富集分析表明暴露于E2后细胞增殖，细胞外基质和细胞运动发生改变。通过多种方法进一步验证，与对照组相比，E2抑制了遗传性腺中的细胞增殖，破坏了细胞外基质并改变了细胞的运动能力，X. laevis。这项研究首次发现了一些早期的分子和细胞事件，雌激素破坏了睾丸的分化并导致X. laevis的女性化。这些新发现提高了我们对雌激素EDC破坏脊椎动物睾丸分化机制的理解。