Clinical application of seminal plasma sperm motility inhibitor.

1. 我们描述了SPMI的初级结构，即对公猪SPMI cDNA基因的编码，对645 bp的SPMI cDNA进行核苷酸序列分析，预测了一个包含137个氨基酸残基的编码多肽，其中包括21个残基的信号肽和116个残基的分泌蛋白。SPMI的氨基酸序列与AQN-3高度同源，AQN-3是野猪精子合成蛋白家族的成员，与精子结合。猪SPMI基因在精囊中的表达量非常丰富，且具有特异性。当SPMI与正常精子反应时，精子活力呈剂量依赖性抑制，当SPMI浓度为1500U/ml时，精子活力被完全抑制。在立即洗涤未动精子后，它们恢复了运动，恢复了30%的运动能力。然而，当SPMI浓度为2000U/ml或更高时，运动能力未恢复。采用抗公猪SPMI抗体在电镜下免疫组化检测其抑制精子活力的机制。SPMI染色在精子细胞膜表面，细胞内不染色。SPMI没有穿透精子细胞膜。这些发现表明，精子不能通过附着在细胞膜上的SPMI进行物理运动，或者附着在SPMI上的精子细胞膜的第二信使抑制了动力蛋白atp酶的活性。人类SPMI前体与Semenogelin I，II相识别。我们研究了不育患者的Semenogelin I、II基因结构是否与有生育能力的男性不同。两名不育患者和一名有生育能力的男性有相同大小的缺失，180bp的Semenogelin I DNA。这种基因缺失在不孕症患者中不是特异性的。

1. We described the primary structure of SPMI,the coding of boar SPMI cDNA gene, Nucleotide sequence analysis of the 645-bp SPMI cDNA predicts a coded polypeptide of 137 amino acid residues which includes a 21-residue signal peptide and a 116 residues secreted protein. The amino acid sequence of SPMI was found to be highly homologous to AQN-3, a member of spermadhesin family proteins of boar that bind to spermatozoa. Expression of the boar SPMI gene detected by Northern blot analysis revealed that its expression is very abundunt in seminal vesicles and specific to this tissue.2. When SPMI was reacted with normal motile sperm, the motility was inhibited in a dose-dependent manner, and completely suppressed at a SPMI concentration of 1500U/ml. After immediate washing of the immotilized sperm, they resumed movement and recovered 30% motility. However, motility was not recovered at a SPMI concentration of 2000U/ml or more. The mechanism of the inhibition of sperm motility was immunohistochemically examined at electron microscopic level using anti-boar SPMI antibody. SPMI was stained on the surface cell membrane of sperm and not stained on inside cell. SPMI did not penetrate the sperm cell membrane. These findings suggest that sperm can not move physically by the attachment of SPMI to cell membrane or second messenger from the sperm cell membrane attached with SPMI inhibits the activity of dynein ATPase.3. Human SPMI precursor identifies with Semenogelin I,II.We investigated whether gene structure of Semenogelin I,II on infertile patients is different with that on fertile men. Two infertile patients and one fertile man had a deletion of same size, 180bp of Semenogelin I DNA.This deletion of gene was not specific in infetile patients.