Compensation for the Lost Prospective Central Nervous System by Expansion of the Prospective Epidermis in the ‘16-Cell’ Embryos of Xenopus laevis Lacking All Animal Dorsal Blastomeres
Compensation for the Lost Prospective Central Nervous System by Expansion of the Prospective Epidermis in the ‘16-Cell’ Embryos of Xenopus laevis Lacking All Animal Dorsal Blastomeres
复制标题
通过扩张缺乏所有动物背卵裂球的非洲爪蟾“16细胞”胚胎中的预期表皮来补偿失去的预期中枢神经系统
DOI：
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发表时间：
1999
期刊：
影响因子：
--
通讯作者：
M. Koga
中科院分区：
文献类型：
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作者：
M. Koga
摘要 在非洲爪蟾的正常胚胎中，中枢神经系统（CNS）和表皮这对主要的外胚层组织分别主要来源于动物背侧（AD）和动物腹侧（AV）卵裂球。尽管未来中枢神经系统存在显着缺陷，但在 16 细胞阶段所有 AD 卵裂球已被去除的缺陷胚胎仍可发育成正常比例的胚胎，即受调控的胚胎。为了比较正常胚胎和调节胚胎之间 AV 卵裂球对 CNS 和表皮的贡献，在 16 细胞阶段通过示踪剂注射标记每个 AV 卵裂球，并检查源自这些外胚层组织中标记卵裂球的克隆结构域。通过去除 AD 卵裂球，每个 AV 卵裂球的克隆域都在背侧方向扩展，不仅像正常胚胎一样覆盖表皮区域，还分别覆盖从前端延伸到后端的 CNS 区域。外胚层组织中大部分丢失的 AD 卵裂球预期区域不是由缺陷胚胎中所有剩余卵裂球的后代补偿的，而是由背侧延伸的 AV 卵裂球的后代补偿的。这些事实表明，对失去的预期中枢神经系统的补偿主要归因于预期外胚层的调节，并且在16细胞阶段之后，通过与胚胎其他部分的相互作用逐步指导预期外胚层的扩散。
Abstract In the normal embryo of Xenopus laevis, the central nervous system (CNS) and epidermis, a pair of main ectodermal tissues, are derived mainly from the animal dorsal (AD) and animal ventral (AV) blastomeres, respectively. The defect embryo, from which all AD blastomeres have been removed at the 16-cell stage, can develop into a normally proportioned embryo, i.e., a regulated embryo, despite the striking deficiency of the prospective CNS. To compare the contribution of the AV blastomeres to the CNS and epidermis between the normal and regulated embryos, each of the AV blastomeres was labelled by a tracer injection at the 16-cell stage, and a clonal domain originating from the labelled blastomere in these ectodermal tissues was examined. By the removal of the AD blastomeres, the clonal domains of the each AV blastomeres were expanded in a dorsal direction, and covered the regions not only in the epidermis just as in normal embryos but also in the CNS extending from the anterior to the posterior end, respectively. Most of the lost prospective regions of the AD blastomeres in the ectodermal tissues were compensated not by the descendants of all the remained blastomeres in the defect embryo, but by the progeny of the AV blastomeres extending dorsally. These facts suggest that compensation for the lost prospective CNS owes mainly to the regulation in the prospective ectoderm, and spreading of the prospective ectoderm is progressively directed after the 16-cell stage by interaction with other parts of the embryo.
影响因子：
2.7
作者：
MOODY, SA
通讯作者：
MOODY, SA
影响因子：
2.7
作者：
MOODY, SA
通讯作者：
MOODY, SA
改进的荧光化合物用于追踪细胞谱系。
影响因子：
2.7
作者：
Gimlich,RL;Braun,J
通讯作者：
Braun,J