ION CURRENTS IN FERTILIZATION AND EARLY DEVELOPMENT

受精首先引发的事件涉及离子变化。 那里 是质膜离子渗透性的立即变化， 细胞内离子浓度的急剧变化。 这些离子 事件必须是激活发展的重要步骤，因为 对蛋内离子环境的简单操控 单性生殖发育。 本研究将研究两者的作用 跨细胞离子电流和细胞内离子浓度的变化 在两个脊椎动物卵中， 青蛙，非洲爪蟾，和鱼Oryzias latipes，使用一些新的 技术：振动探针技术将用于电检测 受精引发的细胞外离子流 Ca ++，H+，Na+， 和Cl-离子浓度将使用细胞内离子特异性 微电极 最早的发育事件之一发生在 受精是一种动态的细胞质再分布，称为"卵质 种族隔离"由于有证据表明这一过程也受到 通过离子电流和梯度，研究这些早期离子的作用， 种族隔离的变化将是这项研究的自然延伸。 的 质膜驱动的稳定的跨细胞离子流 在分离过程中的蛋将被映射， 将被识别。 这项工作的一个主要目标是确定这些 电流在分离机制中起着偶然的作用。

The events first triggered by fertilization involve ionic changes. There is an immediate change in the plasma membrane's ion permeability, as well as a dramatic change in intracellular ion concentrations. These ionic events must be important steps in the activation of development because simple manipulations of the egg's ionc environment will often activate development parthenogenetically. This research will study the role of both transcellular ion currents and intracellular ion concentration changes in activation and ooplasmic segregation in two vertebrate eggs, that of the frog, Xenopus laevis, and the fish Oryzias latipes, using a number of new techniques: Avibrating probe technique will be used to electrically detect the extracellular ion currents triggered by fertilization. Ca++, H+, Na+, and Cl-ion concentrations will be studied using intracellular ion-specific microelectrodes. One of the first developmental events occurring after fertilization is a dynamic cytoplasmic redistribution termed "ooplasmic segregation." Since there is evidence that this process is also influenced by ion currents and gradients, a study of the roles of these early ionic changes in segregation would be a natural extension of this research. The steady transcellular ion currents which the plasma membrane drives through the egg during this segregation will be mapped and the ionic components will be identified. A major goal of this work is to determine if these currents play a casual role in the segregation mechanism.