Structure and function of the N-linked carbohydrate chains of pig zona pellucida glycoproteins.
Structure and function of the N-linked carbohydrate chains of pig zona pellucida glycoproteins.
复制标题
猪透明带糖蛋白 N 连接碳水化合物链的结构和功能。
DOI：
--
复制
发表时间：
1996
期刊：
影响因子：
--
通讯作者：
S. Noguchi
中科院分区：
文献类型：
--
作者：
M. Nakano;N. Yonezawa;Y. Hatanaka;S. Noguchi
竞争实验表明，猪透明带PZP3糖蛋白家族的n链碳水化合物链具有精子受体活性。结构分析表明，n链包括中性和酸性络合型链。中性链中的三或四触角部分具有精子受体活性，但与PZP3相比活性明显降低，表明该蛋白片段参与维持活性链的正确取向。经内切-半乳糖苷酶（E β - G）消化后，PZP3家族的两个组分可以通过反相高效液相色谱分离，其中一个酶解物E β - G-PZP3 α具有精子受体活性。碱处理使E β G-PZP3 α失去o链的活性与E β G-PZP3 α相当，而n -聚糖酶酶切使E β G-PZP3 α失去n链的活性。此外，E β G-PZP3 α的酶切物与赖氨酸内肽酶的竞争分析表明，活性链与PZP3 α的Asn67或Asn84相连，或与两个残基相连。我们得出结论，猪的精卵结合主要是由位于PZP3 α蛋白n端区域的三或四触角、中性、复杂型n -碳水化合物链介导的。
The N-linked carbohydrate chain of the PZP3 glycoprotein family of pig zona pellucida is shown by competition assay to possess sperm receptor activity. Structural analysis reveals that the N-linked chains comprise neutral and acidic complex-type chains. The tri- or tetra-antennary fraction in the neutral chains possesses the sperm receptor activity, but the activity is markedly reduced compared with that of PZP3, suggesting that the protein moiety participates in the maintenance of proper orientation of the active chain. Two components in the PZP3 family can be separated by reverse-phase HPLC after endo-beta-galactosidase (E beta G) digestion and one of the digests, E beta G-PZP3 alpha, possesses the sperm receptor activity. E beta G-PZP3 alpha deprived of O-linked chains by treatment with alkali retains the activity comparable with E beta G-PZP3 alpha, while E beta G-PZP3 alpha deprived of N-linked chains by N-glycanase digestion loses the activity. Furthermore, competition assay of the digests of E beta G-PZP3 alpha with lysyl-endopeptidase indicates that the active chain is linked to Asn67 or Asn84 of PZP3 alpha or to both residues. We conclude that sperm-egg binding in pigs is mainly mediated by tri- or tetra-antennary, neutral, complex-type N-linked carbohydrate chain(s) localized in the N-terminal region of PZP3 alpha protein.