NUCLEO-CYTOPLASMIC INTERACTIONS IN EGGS AND OOCYTES

对早期海胆和海星胚胎细胞周期的控制将 从核质相互作用的角度进行研究。麦长管蚜Aphidicolin 最近发现的一种专门抑制DNA复制的药物将 应用于早期胚胎，与最近开发的 卵子融合技术。这一实验方法旨在使 关于早期胚胎细胞周期控制的几个新确定： (1)未复制核是否对 在细胞周期中的进展；(2)无论细胞的细胞质是否 复制的细胞可以对未复制的细胞核进行正向控制； (3)从这些研究中是否推断出任何控制因素 可以跨越海胆和海星之间的分类障碍。 关于核质相互作用的新发现 仅使用卵子融合技术的未受精卵和未成熟卵母细胞 包括：(4)核DNA复制是否在一种 未受精的海胆卵与受精卵融合后； 未成熟海胆的生发泡是否破裂和成熟 卵母细胞与未受精卵融合后被刺激； 未成熟海星的生发泡破裂和成熟 卵母细胞与成熟的海星卵母细胞融合后被刺激；以及(7) 从这些研究中推断的任何控制因素是否可以 跨越海胆和海星之间的分类障碍。这些 确定应该提供一个更完整的理解如何 在生产过程中，细胞核和细胞质是相互联系的 卵子和胚胎的早期卵裂。

The control of the cell cycle in early sea urchin and starfish embryos will be studied in terms of nucleo-cytoplasmic interactions. Aphidicolin, a recently discovered drug which inhibits DNA replication specifically, will be applied to early embryos in connection with the recently developed technique of egg fusion. This experimental approach is designed to make several new determinations about cell cycle control in the early embryo: (1) whether or not the unreplicated nucleus exerts negative control over progression through the cell cycle; (2) whether or not the cytoplasm of the replicated cell can exert positive control over the unreplicated nucleus; and (3) whether or not any controlling factors inferred from these studies can cross taxonomic class barriers between sea urchins and starfish. Additional new determinations about necleocytoplasmic interactions in unfertilized eggs and immature oocytes using the egg fusion technique only include: (4) whether or not nuclear DNA replication is stimulated in an unfertilized sea urchin egg upon fusion with a fertilized egg; (5) whether or not germinal vesicle breakdown and maturation of an immature sea urchin oocyte is stimulated upon fusion with an unfertilized egg; (6) whether or not germinal vesicle breakdown and maturation of an immature starfish oocyte is stimulated upon fusion with a mature starfish oocyte; and (7) whether or not any controlling factors inferred from these studies can cross taxonomic class barriers between sea urchins and starfish. These determinations should provide a more complete understanding of how the nucleus and cytoplasm are related with one another during the production of the egg and through early cleavage of the embryo.