Institute of Anatomy, Histology and Embryology, Department of Veterinary Sciences, University of Munich, Munich, Germany.
Cells Tissues Organs. 2012;195(4):330-9. doi: 10.1159/000327013. Epub 2011 Jul 19.
The avian inner perivitelline layer (IPVL), a homologous structure to the mammalian zona pellucida, is deposited between the granulosa cells and the oocyte cell membrane during folliculogenesis. The glycoprotein meshwork of the IPVL forms a 3-dimensional matrix and possesses important functions in the fertilization process: it contributes to the binding of avian spermatozoa to the oocyte and induces acrosomal exocytosis. In contrast to the zona pellucida of mammals, the IPVL does not prevent the physiological polyspermy found in birds. Previous studies have shown that in the Japanese quail (Coturnix japonica) at least 5 glycoproteins are constituents of the IPVL (ZP1, ZP2, ZP3, ZP4, and ZPD). In this study, we investigated the spatiotemporal assembly pattern of the IPVL during folliculogenesis using immunohistochemical and ultrastructural methods. The obtained results clearly show that these glycoproteins are incorporated into the IPVL at distinct points during follicular development, supporting the hypothesis that ZP2 and ZP4 form a type of prematrix into which ZP1, ZP3, and ZPD are integrated at a later stage of development.
禽类的内卵周层（IPVL）是卵泡发生过程中在颗粒细胞和卵细胞膜之间沉积的同源结构，类似于哺乳动物的透明带。IPVL 的糖蛋白网状结构形成了一个 3 维基质，在受精过程中具有重要功能：它有助于禽类精子与卵母细胞的结合，并诱导顶体反应。与哺乳动物的透明带不同，IPVL 并不阻止鸟类中发现的生理性多精入卵。先前的研究表明，在日本鹌鹑（Coturnix japonica）中，至少有 5 种糖蛋白是 IPVL（ZP1、ZP2、ZP3、ZP4 和 ZPD）的组成部分。在这项研究中，我们使用免疫组织化学和超微结构方法研究了卵泡发生过程中 IPVL 的时空组装模式。获得的结果清楚地表明，这些糖蛋白在卵泡发育的不同时间点被整合到 IPVL 中，支持 ZP2 和 ZP4 形成一种前基质的假说，ZP1、ZP3 和 ZPD 在后一阶段的发育过程中被整合到其中。
