Mozingo N M, Chandler D E
Department of Zoology, Arizona State University, Tempe 85287.
Dev Biol. 1991 Jul;146(1):148-57. doi: 10.1016/0012-1606(91)90455-c.
The sea urchin fertilization envelope (FE) is a complex, macromolecular aggregate assembled by the addition of cortical granule secretions to the vitelline layer. The completed, trilaminar structure has a dense layer sandwiched between surface coats of paracrystalline material. Two cortical granule enzymes, ovoperoxidase and protease, and a cell surface transglutaminase are required for the assembly process. We have examined, by quick-freeze, deep-etch, rotary-shadow electron microscopy, the effects of inhibiting each of these enzymes upon FE assembly. These experiments reveal two domains within the FE, distinguishable by their enzymatic requirements for proper maturation. The first domain consists of the microvillar casts which require both protease and transglutaminase activities to obtain a normal paracrystalline coat. The second domain comprises the regions between casts and appears to mature by ovoperoxidase-mediated cross-linking of paracrystalline material to the envelope.
海胆受精膜（FE）是一种复杂的大分子聚集体，通过将皮质颗粒分泌物添加到卵黄膜层而组装形成。完整的三层结构有一层致密层夹在准晶体材料的表面涂层之间。组装过程需要两种皮质颗粒酶，即卵过氧化物酶和蛋白酶，以及一种细胞表面转谷氨酰胺酶。我们通过快速冷冻、深度蚀刻、旋转阴影电子显微镜检查了抑制这些酶中的每一种对受精膜组装的影响。这些实验揭示了受精膜内的两个区域，可根据它们正常成熟所需的酶来区分。第一个区域由微绒毛铸型组成，其需要蛋白酶和转谷氨酰胺酶的活性才能获得正常的准晶体涂层。第二个区域包括铸型之间的区域，似乎是通过卵过氧化物酶介导的准晶体材料与膜的交联而成熟。
