Ungefroren H, Ergün S, Krull N B, Holstein A F
Institute of Anatomy, University of Hamburg, Germany.
Biol Reprod. 1995 May;52(5):1095-105. doi: 10.1095/biolreprod52.5.1095.
The genes coding for the core proteins of the small chondroitin sulfate/dermatan sulfate proteoglycans (PGs) biglycan and decorin are both expressed in the adult human testis. Northern hybridization of human testicular mRNA indicated the presence of one specific transcript for biglycan at 2.6 kb and two specific transcripts for decorin at 1.6 kb and 1.9 kb. In situ hybridization localized the mRNA for biglycan to the peritubular tissue as well as to the tunica muscularis and adventitia of arteries. Leydig cells and cells of the seminiferous epithelium both proved to be negative. For decorin mRNA, strong signals were found over single, dispersed interstitial cells (possibly fibroblasts), the adventitious layer of large arteries, and the perivascular tissue cells of small arteries, arterioles, and capillaries. In the peritubular cell layers, decorin gene expression was comparably lower and was restricted to the outer fibroblast layers. Germ cells and Sertoli cells were devoid of any positive signal. Immunoblot analysis using specific antisera directed against the core proteins of biglycan and decorin confirmed their presence in chondroitin ABC lyase-treated proteinaceous extracts of the human testis. Immunohistochemistry for biglycan showed a good spatial correlation with the in situ hybridization data and revealed in addition a nonuniform distribution of the antigenic material, which was located predominantly over peritubular myoid cells and the adventitious layer of arteries. Together these results indicate that the expression of both genes in the human testis is differentially regulated, despite the overall similarity of their protein products, and suggest distinct roles for these PGs in testicular function.
编码小硫酸软骨素/硫酸皮肤素蛋白聚糖（PGs）双糖链蛋白聚糖和核心蛋白聚糖核心蛋白的基因在成年人类睾丸中均有表达。人睾丸mRNA的Northern杂交表明，双糖链蛋白聚糖有一个2.6 kb的特异性转录本，核心蛋白聚糖有两个特异性转录本，分别为1.6 kb和1.9 kb。原位杂交将双糖链蛋白聚糖的mRNA定位到睾丸白膜组织以及动脉的肌层和外膜。睾丸间质细胞和生精上皮细胞均为阴性。对于核心蛋白聚糖mRNA，在单个分散的间质细胞（可能是成纤维细胞）、大动脉的外膜层以及小动脉、微动脉和毛细血管的血管周围组织细胞中发现了强信号。在睾丸白膜细胞层中，核心蛋白聚糖基因表达相对较低，且仅限于外层成纤维细胞层。生殖细胞和支持细胞没有任何阳性信号。使用针对双糖链蛋白聚糖和核心蛋白聚糖核心蛋白的特异性抗血清进行的免疫印迹分析证实了它们存在于经软骨素ABC裂解酶处理的人类睾丸蛋白质提取物中。双糖链蛋白聚糖的免疫组织化学显示与原位杂交数据有良好的空间相关性，此外还揭示了抗原物质的不均匀分布，其主要位于睾丸白膜肌样细胞和动脉外膜层。这些结果共同表明，尽管这两种基因的蛋白质产物总体相似，但它们在人类睾丸中的表达受到不同的调节，并提示这些PGs在睾丸功能中具有不同的作用。
