Pan J, Sasanami T, Nakajima S, Kido S, Doi Y, Mori M
Department of Applied Biological Chemistry, Faculty of Agriculture, Shizuoka University, Shizuoka, Japan.
Mol Reprod Dev. 2000 Feb;55(2):175-81. doi: 10.1002/(SICI)1098-2795(200002)55:2<175::AID-MRD6>3.0.CO;2-6.
The inner layer of the vitelline membrane of avian oocyte is equivalent to the zona pellucida of mammalian oocytes or to the vitelline envelope of amphibian oocytes. One of the two major glycoproteins in the inner layer of quail vitelline membrane, formerly called 33-kDa glycoprotein, is homologous to mammalian ZPC, one of the components of zona pellucida. Quail ZPC is found to have different mobilities on SDS-polyacrylamide gel electrophoresis depending on whether it is obtained from the preovulatory follicle or from the laid eggs. In order to characterize the progressive changes in the molecular size of quail ZPC during the oviductal transport, the inner layer isolated from the follicle was incubated in vivo in various regions of the oviduct and subjected to Western blot analysis with anti-quail ZPC antiserum. The quail ZPC of the inner layer incubated in infundibulum reduced its apparent molecular weight, exhibiting the same electrophoretic mobility as that of laid eggs. The similar reduction in molecular weight was observed after the in vitro incubation of the inner layer with the extracts of infundibulum. From the comparison of the N-terminal amino acid sequences, it was found that the first 26 residues of the quail ZPC in follicular oocytes are missing from the ZPC of laid eggs. In addition, lectin blot analysis suggested the modification of oligosaccharide chains during the oviductal transport. These results represent the first description in the avian oviduct of the presence of protease, which is similar to oviductin, a trypsin-like protease involved in the hydrolysis of a major component of the vitelline envelope of amphibian oocytes. Mol. Reprod. Dev. 55:175-181, 2000.
禽卵母细胞卵黄膜的内层相当于哺乳动物卵母细胞的透明带或两栖动物卵母细胞的卵黄膜。鹌鹑卵黄膜内层的两种主要糖蛋白之一，以前称为33 kDa糖蛋白，与哺乳动物透明带的成分之一ZPC同源。发现鹌鹑ZPC在SDS-聚丙烯酰胺凝胶电泳上具有不同的迁移率，这取决于它是从排卵前卵泡中获得还是从产下的卵中获得。为了表征鹌鹑ZPC在输卵管运输过程中分子大小的渐进变化，将从卵泡中分离出的内层在输卵管的各个区域进行体内孵育，并用抗鹌鹑ZPC抗血清进行蛋白质免疫印迹分析。在内漏斗中孵育的内层鹌鹑ZPC降低了其表观分子量，表现出与产下的卵相同的电泳迁移率。在内层与漏斗提取物进行体外孵育后，也观察到了类似的分子量降低。通过比较N端氨基酸序列，发现卵泡卵母细胞中鹌鹑ZPC的前26个残基在产下的卵的ZPC中缺失。此外，凝集素印迹分析表明在输卵管运输过程中寡糖链发生了修饰。这些结果首次描述了禽输卵管中存在一种蛋白酶，它类似于输卵管蛋白酶，一种参与两栖动物卵母细胞卵黄膜主要成分水解的胰蛋白酶样蛋白酶。《分子生殖与发育》55:175 - 181，2000年。
