Sea urchin (Mesocentrotus nudus) is an important economically mariculture species in several Asian countries, and gonads are the sole edible parts for people. In addition to commercial value, it is an excellent model for studying gonadal development, sex determination and sex differentiation. Identify sex-related genes is an effective way to reveal the molecular mechanism of gonadal development. In the present study, the foxl2 homologous gene was identified in M. nudus. Foxl2 is not a maternal factor, and is detected for the first time in two-arm stages. Additionally, the expression of foxl2 in the testis is higher than in the ovaries at the same developmental stages. The foxl2 transcripts were specifically enriched in the cytoplasm of germ cellsboth in the ovary and testis, but their proteins were more concentrated in the area near the oocyte nucleus. Overall, this study contributes to our understanding of the dynamic and sexually dimorphic expression pattern of foxl2 and provide a useful germ cell marker during gametogenesis in sea urchin.

海胆（Mesocentrotus nudus）是亚洲几个国家重要的经济海水养殖物种，性腺是人类唯一可食用的部分。除了商业价值外，它还是研究性腺发育、性别决定和性别分化的绝佳模型。识别性相关基因是揭示性腺发育分子机制的有效途径。在本研究中，foxl2同源基因在M. nudus 中被鉴定。Foxl2不是母体因素，首次在双臂阶段检测到。此外，在相同发育阶段，foxl2在睾丸中的表达高于卵巢。foxl2 _转录本特别富集在卵巢和睾丸生殖细胞的细胞质中，但它们的蛋白质更集中在卵母细胞核附近的区域。总的来说，这项研究有助于我们理解foxl2的动态和两性异形表达模式，并在海胆配子发生过程中提供有用的生殖细胞标记。