Research Institute of Fish Culture and Hydrobiology, South Bohemian Research Center of Aquaculture and Biodiversity of Hydrocenoses, Faculty of Fisheries and Protection of Waters, University of South Bohemia in Ceske Budejovice, Vodnany, Czech Republic.
Biol Reprod. 2018 Sep 1;99(3):556-564. doi: 10.1093/biolre/ioy076.
A technique for rescuing and propagating endangered species involves implanting germ line stem cells into surrogates of a host species whose primordial germ cells (PGCs) have been destroyed. We induced sterilization in sterlet (Acipenser ruthenus) embryos by means of ultraviolet (UV) irradiation at the vegetal pole, the source of early-stage PGCs of sturgeon eggs. The optimal cell stage and length of UV irradiation for the effective repression of the developing PGCs were determined by exposing embryos at the one- to four-cell stage to different doses of irradiation at a wavelength of 254 nm (the optimal absorbance spectrum for germplasm destruction). The vegetal pole region of the embryos was labeled immediately upon irradiation with GFP bucky ball mRNA to monitor the amount of germ plasm and FITC-dextran (M.W. 500,000) to obtain the number of PGCs in the embryos. The size of the germ plasm and number of surrounding mitochondria in the irradiated embryos and controls were observed using transmission electron microscopy, which revealed a drastic reduction in both on the surface of the vegetal pole in the treated embryos. Furthermore, the reduction in the number of PGCs was proportional to the dose of UV irradiation. Under the conditions tested, optimum irradiation for PGCs removal was seen at 360 mJ/cm2 at the one-cell stage. Although some PGCs were observed after the UV irradiation, they significantly reduced in number as the embryos grew. We conclude that UV irradiation is a useful and efficient technique to induce sterility in surrogate sturgeons.
一种拯救和繁殖濒危物种的技术涉及将生殖系干细胞植入宿主物种的代孕体中，这些代孕体的原始生殖细胞（PGC）已被破坏。我们通过在植物极（鲟鱼卵中早期 PGC 的来源）用紫外线（UV）照射来诱导小体（Acipenser ruthenus）胚胎绝育。通过将胚胎暴露在单细胞至四细胞阶段，用波长为 254nm 的不同剂量照射（破坏种质的最佳吸收光谱），确定了有效抑制发育中的 PGC 所需的最佳细胞阶段和 UV 照射时间长度。照射后，立即用 GFP 巴克球 mRNA 标记胚胎的植物极区域，以监测种质的数量和 FITC-葡聚糖（MW500,000），以获得胚胎中 PGC 的数量。用透射电子显微镜观察照射和对照胚胎中种质的大小和周围线粒体的数量，结果显示在处理胚胎的植物极表面急剧减少。此外，PGC 数量的减少与 UV 照射剂量成正比。在所测试的条件下，在单细胞阶段 360mJ/cm2 时观察到 PGC 去除的最佳照射。尽管在 UV 照射后观察到一些 PGC，但随着胚胎的生长，它们的数量明显减少。我们得出结论，紫外线照射是一种在代孕鲟鱼中诱导不育的有用且有效的技术。
