短额负蝗卵子发生过程中糖复合物的动态分布

以生物素标记的凝集素(UEA-I、SBA、PNA)为探针,利用凝集素组织化学方法对短额负蝗(Atracto-morphasinensis)卵子发生过程中滤泡细胞和卵母细胞内糖复合物的分布进行了定位研究。结果表明,在卵子发生的各期滤泡细胞和卵母细胞中没有UEA-I受体的表达,SBA和PNA受体以不同的分布模式呈阶段性表达。两者首次出现于卵母细胞生长期,随后PNA受体消失,SBA受体大量表达;在卵黄形成期前期SBA受体和重新出现的PNA受体表达于卵黄颗粒形成部位,卵黄形成期后期两者均为阴性表达;成熟卵子中两种受体又以不同程度重新出现于卵黄膜。两种受体在滤泡细胞内均大量表达。提示,N-乙酰半乳糖胺和半乳糖-β-(1,3)半乳糖胺复合物的修饰和变化与卵母细胞的发育、卵黄物质的形成及滤泡细胞的增殖分化密切相关,卵黄膜上的糖复合物可能与精卵识别有关。

Dynamic Distribution of Glycoconjugates During Oogenesis of Atractomorpha sinensis

The dynamic distribution of three different glycoconjugates in oocytes and follicle cells during the oogenesis of Atractomorpha sinensis were detected using biotin-labeled Peanut Agglutinin (PNA), Soy Bean Agglutinin (SBA) and Ulex Europaeus Agglutinin I (UEA-I) lectins. The results showed that during oogenesis there was no distribution of the UEA-I receptor. The receptors of PNA and SBA were found to be dependent on developmental stage and present different distribution patterns accordingly. The binding sites of the two lectins indicated the presence of different sugars (PNA for Galβ1,3GalNAc and SBA for GalNAc) and showed considerable variation during oogenesis. PNA and SBA receptors first appeared at the oocyte growth phase, the PNA receptors then disappeared gradually and the SBA receptors exhibited the greatest expression. At the early phase of yolk formation, PNA and SBA receptors were located just at the brim of ooplasm, which was the region of vitellin formation. However at the later phase of yolk formation, neither of the two receptors was detected. In the mature egg, PNA and SBA receptors were distributed again on the vitellin membrane and the eggshell. The two receptors were also widely distributed in the follicular cells, showing similar distribution variation to the oocytes. The results indicate that the change and modification of the two receptors may be greatly related to the growth of oocytes, the preparation for yolk formation, the differentiation of follicular cells and the maturation of oocytes. The glycoconjugates on the vitellin membrane probably play important roles in sperm and egg recognition.The two lectins bound moderately or strongly to the eggshell, which indicates that the eggshell of A. sinensis contains the GalNAc and Galβ1,3GalNAc glycoproteins.