CHARACTERIZATION OF SUGAR CHAINS LINKED TO EPIDIDYMAL PLASMA ANTI AGGLUTININ

哺乳动物精子头对头凝集性的降低 在附睾中的变化被认为是与 精子成熟，并与调节 精子生育能力 我们以前报道过猪唾液酸糖蛋白 附睾血浆抗凝集素（epidididymal plasma anti-agglutinin，EPAA）是附睾炎的调节因子之一， EPAA与精子相互作用， 依赖于翻译后修饰的程度， 分子。 目前的目标是描述主要的 EPAA结构、糖基化和磷酸化（质量） 光谱法 通过质谱分析获得的结果为： 如下所示. 1. EPAA的分子量为19379 Da（ESI-MS）， 与SDS-PAGE（25 kDa）的结果不同。 此外，类似的 获得了从精液中纯化的抗凝集素的质谱 血浆，表明EPAA的结构几乎没有变化，在这一点上， 成熟阶段。 2. 去糖基化后EPAA的质谱 和胰蛋白酶消化（肽质量指纹）（ESI MS）是独特的， 这表明EPAA是一种新的蛋白质。 这一建议已经 通过N-末端氨基酸序列分析证实。 3. 比较 去糖基化前后EPAA的质谱（MALDI-MS） 表明EPAA没有严重糖基化，但糖基化是 礼物 4. 磷酸化的研究正在进行中。 这些 结果（1-3）提供了有关监管的有价值的信息 精子凝集性降低的机制。

Reduction of head-to-head agglutinability of mammalian spermatozoa in the epididymis has been considered to be one of changes related to sperm maturation and to be associated with regulation of expression of sperm fertility. We previously reported that boar sialoglycoprotein (epididymal plasma anti-agglutinin) (EPAA) was one of regulators of agglutinability and that interaction of EPAA with spermatozoa was dependent on degree of posttranslational modifications in this molecule. The present objective was to characterize the primary structure, glycosylation and phosphorylation of EPAA by mass spectrometry. The results obtained by mass spectrometric analysis are shown below. 1. EPAA has molecular mass of 19379 Da (ESI-MS), which is different from that estimated by SDS-PAGE (25 kDa). Also,a similar mass spectrum was obtained for anti-agglutinin purified from seminal plasma, indicating almost no change in the structure of EPAA in this stage of maturation. 2. Mass spectra of EPAA after deglycosylation and tryptic digestion (peptide mass fingerprint) (ESI MS) are unique, suggesting EPAA is a novel protein. This suggestion has been already confirmed by N-terminal amino acid sequence analysis. 3. Comparison of mass spectra of EPAA before and after deglycosylation (MALDI-MS) reveals that EPAA is not heavily glycosylated, but glycosylation is present. 4. Research on phosphorylation is in progress now. These results (1-3) have provided valuable information on the regulatory mechanism of the reduction of sperm agglutinability.