Biochemical characterization of a glycosylphosphatidylinositol-linked hyaluronidase on mouse sperm.
Biochemical characterization of a glycosylphosphatidylinositol-linked hyaluronidase on mouse sperm.
复制标题
小鼠精子上糖基磷脂酰肌醇连接的透明质酸酶的生化特征。
DOI：
10.1021/bi00024a002
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发表时间：
1995
期刊：
影响因子：
2.9
通讯作者：
Cardullo,RA
中科院分区：
文献类型：
--
作者：
Thaler,CD;Cardullo,RA
摘要：基于与蜂毒透明质酸酶的DNA同源性，最近提出GPI-连接的哺乳动物精子抗原PH-20可以作为细胞表面透明质酸酶起作用[Gmachl，M.，& Kreil，G.等人（1993）Proc. Acad. Sci.联合SA. 90，3569-3573]。我们已经量化了小鼠精子的可溶性顶体透明质酸酶的活性，并进一步证明了膜结合透明质酸酶的存在，顶体完整和顶体反应的小鼠精子上检测到，不同于可溶性形式的酶。膜结合的透明质酸酶被PI-PLC特异性释放，表明它是GPI连接的。顶体完整和顶体反应的精子释放几个多肽（68，44，39，34，17，和15 kDa）时，与PI-PLC处理。此外，GPI连接的多肽独特的顶体完整或顶体反应的精子被确定。使用尺寸排阻色谱法从顶体反应的精子中分离PI-PLC释放的组分，显示了透明质酸酶活性的单峰，其与这些组分中存在的68 kDa GPI连接的蛋白质共迁移。两者合计，这些数据表明存在至少两种异构体的透明质酸酶：可溶性形式的顶体囊泡内的顶体胞吐过程中释放和GPI连接的形式，这是存在于顶体完整和顶体反应的精子的表面上。这两种形式都可能是成功穿透受精前卵细胞外膜所必需的。
Revised Manuscript Received April 12, 1995® abstract: On the basis of DNA homology to bee venom hyaluronidase, it was recently suggested that the GPI-linked mammalian sperm antigen, PH-20, may function as a cell surface hyaluronidase [Gmachl, M., & Kreil, G.(1993) Proc. Natl. Acad. Sci. U. SA. 90, 3569—3573]. We have quantified the activity of the soluble acrosomal hyaluronidase of mouse sperm and further demonstrate the existence of a membrane-bound hyaluronidase, detected on both acrosome-intact and acrosome-reacted mouse sperm, distinct from the soluble form of the enzyme. The membrane-bound hyaluronidase was specifically released by PI-PLC, indicating that it is GPI linked. Acrosome-intact and acrosome-reacted sperm released several polypeptides (68, 44, 39, 34, 17, and 15 kDa) when treated with PI-PLC. In addition, GPI-linked polypeptides unique to acrosome-intact or to acrosome-reacted sperm were identified. Fractionation of the PI-PLC-released components from acrosome-reacted sperm using size exclusion chromatography revealed a single peak of hyaluronidase activity which comigrates with a 68 kDa GPI-linked protein present in these fractions. Taken together, these data demonstrate the existence of at least two isoforms of hyaluronidase: a soluble form within the acrosomal vesicle which is released during acrosomal exocytosis and a GPI-linked form which is present on the surface of both acrosome-intactand acrosome-reacted sperm. Both forms may be necessary for successful penetration of the extracellular vestments that surround the egg prior to fertilization.