PDF(Pubmed)
Abstract：
Sea urchins are usually gonochoristic, with all of their five gonads either testes or ovaries. Here, we report an unusual case of hermaphroditism in the purple sea urchin, Strongylocentrotus purpuratus. The hermaphrodite is self-fertile, and one of the gonads is an ovotestis; it is largely an ovary with a small segment containing fully mature sperm. Molecular analysis demonstrated that each gonad producedviable gametes, and we identified for the first time a somatic sex-specific marker in this phylum: Doublesex and mab-3 related transcription factor 1 (DMRT1). This finding also enabled us to analyze the somatic tissues of the hermaphrodite, and we found that the oral tissues (including gut) were out of register with the aboral tissues (including tube feet) enabling a genetic lineage analysis. Results from this study support a genetic basis of sex determination in sea urchins, the viability of hermaphroditism, and distinguish gonad determination from somatic tissue organization in the adult.
摘要：
海胆通常是淋病的，它们的五个性腺都是睾丸或卵巢。在这里，我们报告了紫色海胆中雌雄同体的不寻常病例，紫癜。雌雄同体是自育的，其中一个性腺是卵睾丸；它主要是一个卵巢，一小部分含有完全成熟的精子。分子分析表明，每个性腺都能产生真正的配子，我们首次在这个门类中发现了一个体细胞性别特异性标记：双雄直系同源，DMRT1.这一发现还使我们能够分析雌雄同体的体细胞组织，我们发现口腔组织（包括肠道）与流产组织（包括管足）不一致，从而可以进行遗传谱系分析。这项研究的结果支持海胆性别决定的遗传基础，雌雄同体的生存能力，并将性腺测定与成人的躯体组织区分开来。
