PLASMA MEMBRANE CHANGES IN FERTILIZATION

本研究的总体目标是表征 海胆卵的细胞表面，并阐明这些作用， 在受精的初始事件的成分。 1)我们将继续 研究了从卵中分离的细胞表面复合物的组分， 由质膜组成，其外侧涂有外周 卵黄层和皮质内侧的蛋白质 囊泡 进一步细分卵黄成分后， 质膜、皮层小泡膜和细胞内含物 将分离皮质囊泡，并进行比较分析， 多肽、脂质和标记酶。 更清楚地了解 这些成分在受精后的命运， 透明层和受精膜的已知成分。 2)从质膜制备的囊泡的离子渗透性， 皮层小泡膜和由两者组成的镶嵌膜 将被测量，以确定是否这些膜之一是负责 Ca ~（++）和Na ~（++）进入卵细胞的增加， 受精 3)我们将研究Ca++依赖性 分解和花生四烯酸释放。 所述细胞表面复合物可以是微球。 一个很好的模型来研究动力学和功能之间的关系， 分泌和花生四烯酸的产生和代谢。 4)结构 研究了鸡蛋皮中硫酸多糖的含量， 导致物种特异性诱导的结构差异 精子顶体反应。 使用果冻衣作为亲和配体， 将负责分离精子表面的蛋白质 它的功能是作为果冻外套的受体。 的性质和模式 分离的受体在诱导顶体反应中的作用将是 研究了 5)使用结合或针对糖肽制备的抗体 作为工具，我们将分离精子的受体 来自溶解的卵细胞表面膜。 纯化的受体将是 其特征和结构组成部分，它负责 将定义精子粘附和种属特异性。

The overall objective of this study is to characterize the components of the cell surface of the sea urchin egg and to elucidate the role of these components in the initial events in fertilization. 1) We will continue studies on the components of a cell surface complex isolated from eggs that consists of the plasma membrane, coated on the outer side with peripheral proteins of the vitelline layer and on the inner side with cortical vesicles. Following further subfractionation the vitelline components, plasma membrane, cortical vesicle membrane, and the contents of the cortical vesicles will be isolated, and analyzed comparatively for polypeptides, lipids, and marker enzymes. To obtain a clearer picture of the fate of these components following fertilization, they will be compared with known components of the hyaline layer and the fertilization envelope. 2) The ion permeability of vesicles prepared from the plasma membrane, the cortical vesicle membrane and a mosaic membrane consisting of both of them will be measured to determine if one of these membranes is responsible for the enhanced influx of Ca++ and Na+ into the egg observed upon fertilization. 3) We will investigate the possibility that Ca++ dependent breakdown and arachidonic acid release. The cell surface complex may be an excellent model to study the kinetic and functional relationships between secretion and arachidonic acid production and metabolism. 4) The structure of the sulfated polysaccharides in egg jelly coat will be studied to define the structural differences that result in species specific induction of the acrosomal reaction in sperm. Using jelly coat as an affinity ligand we will undertake the isolation of the protein on the surface of the sperm that functions as a receptor of jelly coat. The properties and mode of action of the isolated receptor in inducing the acrosomal reaction will be studied. 5) Using binding, or antibody prepared towards a glycopeptide fragment of the receptor as tools, we will isolate the receptor for sperm from solubilized egg cell surface membranes. The purified receptor will be characterized and the structural components of it responsible for both sperm adhesion and species specificity will be defined.