Restriction of Germline Proliferation by Soft X-ray Irradiation of Chicken Embryos and its Application to Chimera Production
Restriction of Germline Proliferation by Soft X-ray Irradiation of Chicken Embryos and its Application to Chimera Production
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DOI：
10.2141/jpsa.45.292
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发表时间：
2008-10-01
影响因子：
1.5
通讯作者：
Ono, Tamao
中科院分区：
文献类型：
--
作者：
Atsumi, Yusuke;Tagami, Takahiro;Ono, Tamao
原始生殖细胞（PGC）是配子的祖细胞。禽类 PGC 位于胚盘阶段透明区的中央区域。 PGC 在孵化蛋中形成血管后不久就进入循环系统，并最终定居在性腺原基中。我们现在已经研究了将鸡胚胎暴露于软（低能量）X 射线作为消耗内源性 PGC 的一种手段，从而提高嵌合体生产的效率。白来航蛋的胚盘在孵化前接受软 X 射线照射 0、20、40 或 60 秒。受辐射的胚胎在孵化60小时时表现出发育延迟。他们还显示，第 14 和 15 阶段的循环 PGC 数量以及第 30 阶段的性腺 PGC 数量减少。受辐射胚胎的孵化率低于未辐射对照胚胎。考虑到 PGC 增殖和孵化率的限制，发现照射 20 秒可提供最佳结果。将鹌鹑（黑色羽毛）胚胎的分散胚盘细胞引入照射20秒的鸡胚胎或未照射胚胎的胚盘中。在第 30 阶段，受辐射胚胎中供体来源的 PGC 数量高于未受辐射对照。这些结果表明，鸡胚胎的软 X 射线辐射是消除内源生殖细胞并随后提高供体 PGC 掺入效率的可行方法。
Primordial germ cells (PGCs) are the progenitor cells of gametes. Avian PGCs are located in the central region of the area pellucida at the blastoderm stage. PGCs enter the circulation soon after the formation of blood vessels in incubating eggs and eventually settle in the gonadal primordium. We have now examined exposure of chicken embryos to soft (low-energy) x-rays as a means of depleting endogenous PGCs and thereby improving the efficiency of chimera production. The blastoderm of White Leghorn eggs was exposed to soft x-rays for 0, 20, 40 or 60s before incubation. The irradiated embryos manifested delayed development at 60 h of incubation. They also showed reduced numbers of circulating PGCs at stages 14 and 15 and of gonadal PGCs at stage 30. The hatchability of irradiated embryos was lower than that of nonirradiated controls. Irradiation for 20 s was found to provide the best outcome taking into consideration both the restriction of PGC proliferation and hatchability. Dispersed blastoderm cells of quail (black plumage) embryos were introduced into the blastoderm of chicken embryos irradiated for 20 s or of nonirradiated embryos. The number of donor-derived PGCs was higher in the irradiated embryos than in the nonirradiated controls at stage 30. These results suggest that soft x-irradiation of chicken embryos is a feasible approach to depletion of endogenous germ cells and consequent improvement in the efficiency of incorporation of donor PGCs.