Rat sperm surface mannosidase is first expressed on the plasma membrane of testicular germ cells.
Rat sperm surface mannosidase is first expressed on the plasma membrane of testicular germ cells.
复制标题
大鼠精子表面甘露糖苷酶首先在睾丸生殖细胞的质膜上表达。
DOI：
10.1095/biolreprod59.6.1288
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发表时间：
1998
影响因子：
3.6
通讯作者：
Tulsiani,DR
中科院分区：
文献类型：
--
作者：
Pereira,BM;Abou-Haila,A;Tulsiani,DR
在先前的出版物（Tulsiani等人，Biochem J 1993; 290：427-436和Tulsiani等人，Dev Biol 1995; 167：584-595），我们报道了精子表面甘露糖苷酶存在于大鼠睾丸中，并且在精子发生和精子成熟期间被修饰。目前的研究是针对检查α-D-甘露糖苷酶活性的起源存在于可育精子。用2-4%线性牛血清白蛋白梯度离心分离大鼠睾丸酶消化后的混合生殖细胞。分别合并精母细胞、圆形精子细胞和浓缩/伸长精子细胞（> 95%纯细胞）中富集的级分，并在用Triton X-100裂解之前（完整）和之后测定[3 H] Man 9-甘露糖苷酶活性。有趣的是，这些细胞含有显著水平的α-d-甘露糖苷酶活性。洗涤剂溶解的生殖细胞提取物中约70%的总[3 H] Man 9-甘露糖苷酶活性与抗大鼠精子甘露糖苷酶交叉反应，25%的活性与抗高尔基甘露糖苷酶I交叉反应。该结果表明，生殖细胞提取物中存在的大部分甘露糖苷酶活性与尾部精子上存在的酶在抗原性上相似。使用细胞分级分离技术，我们获得的证据表明，生殖细胞相关的甘露糖苷酶活性是质膜的一个组成部分。综上所述，这些结果表明精子表面甘露糖苷酶首先在睾丸生殖细胞上表达。
In previous publications (Tulsiani et al., Biochem J 1993; 290:427–436 and Tulsiani et al., Dev Biol 1995; 167:584–595), we reported that sperm surface mannosidase is present in rat testis and is modified during spermatogenesis and sperm maturation. The present studies were directed towards examining the origin of α-d-mannosidase activity present on fertile spermatozoa. Mixed germ cells prepared after sequential enzymatic digestions of rat testis were separated by unit gravity sedimentation using 2–4% linear bovine serum albumin gradient. Fractions enriched in spermatocytes, round spermatids, and condensed/elongated spermatids (> 95% pure cells) were separately pooled and assayed for [3H]Man9-mannosidase activity before (intact) and after lysis with Triton X-100. Interestingly, the cells contained a significant level of α-d-mannosidase activity. Approximately 70% of the total [3H]Man9-mannosidase activity present in the detergent-solubilized germ cell extract cross-reacted with anti-rat sperm mannosidase, and 25% of the activity cross-reacted with anti-Golgi mannosidase I. This result indicates that most of the mannosidase activity present in the germ cell extract is antigenically similar to the enzyme present on the cauda spermatozoa. Using cell fractionation techniques, we obtained evidence suggesting that the germ cell-associated mannosidase activity is an integral component of the plasma membranes. Taken together, these results indicate that sperm surface mannosidase is first expressed on the testicular germ cells.