Acid hydrolases of the epidermis: subcellular localization and relationship to cornification.
Acid hydrolases of the epidermis: subcellular localization and relationship to cornification.
复制标题
表皮酸性水解酶：亚细胞定位及其与角化的关系。
DOI：
10.1111/1523-1747.ep12555534
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发表时间：
1983
期刊：
影响因子：
--
通讯作者：
Traczyk,TN
中科院分区：
文献类型：
--
作者：
Freinkel,RK;Traczyk,TN
在胎鼠发育表皮的亚细胞部分中检查了三种溶酶体型酸性水解酶，以评估降解酶与角质化的关系。随着妊娠 18 至 20 天 (D) 期间颗粒层发育和角化，表皮酸性磷酸酶增加，酸性磷脂酶 A 保持恒定，β-葡萄糖醛酸酶活性下降。这些酶存在于 3,000、17,000 和 100,000 g 颗粒级分和可溶性细胞质中。然而分布不同：在 17,000 g 级分中，酸性磷酸酶和磷脂酶 A 比葡萄糖醛酸酶更优先定位，该级分排除了线粒体和核糖体，并富含层状颗粒。研究结果表明，酸性磷酸酶和磷脂酶存在于颗粒层的膜结合细胞器（例如层状颗粒）中。第 19 天和第 20 天，颗粒状酸性磷酸酶随颗粒层增加，而第 20 天，可溶性酶增加 7 倍，与角化一致。如等电聚焦所示，酶在第 20 天比第 18 天变得更加异质，表明糖基化增加。颗粒部分在酸性磷酸酶的释放方面表现出溶酶体特征，该酶被氢化可的松抑制并被视黄醇增强。当胎儿表皮在器官培养物中角化时，酸性磷酸酶也出现类似的增加。氢化可的松的存在不影响总酶的增加，但较大比例保留在颗粒部分中。研究结果表明，在颗粒细胞的发育过程中，颗粒酸性磷酸酶和磷脂酶被划分在具有溶酶体特征的细胞器中，并且磷酸酶的释放与角化同时发生。这可能不仅反映了层状颗粒的胞吐作用，而且还反映了水解酶的细胞内释放。
Three lysosomal-type acid hydrolases were examined in subcellular fractions of the developing epidermis of fetal rats to assess the relationship of degradative enzymes to cornification. As the granular layer developed and cornified between 18 and 20 days (D) of gestation, epidermal acid phosphatase increased, acid phospholipase A remained constant, and β-glucuronidase activity declined. The enzymes were present in 3,000, 17,000, and 100,000 g particulate fractions and soluble cytoplasm. However distribution differed: acid phosphatase and phospholipase A were more preferentially localized than was glucuronidase in the 17,000 g fraction which excluded mitochondria and ribosomes and was enriched in lamellar granules. The findings suggested that acid phosphatase and phospholipase were present in membrane-bound organelles (e.g., lamellar granules) in the granular layer. Particulate acid phosphatase increased with granular layers on days 19 and 20 while a 7-fold increase in soluble enzyme coincided with cornification on day 20. As shown by isoelectric focusing, the enzyme became more heterogeneous at day 20 than at day 18, suggesting increased glycosylation. The particulate fraction displayed lysosomal characteristics with respect to release of acid phosphatase, which was inhibited by hydrocortisone and enhanced by retinol. When fetal epidermis was allowed to cornify in organ cultures, similar increases in acid phosphatase occurred. The presence of hydrocortisone did not affect increase in total enzyme but a greater proportion remained in the particulate fraction. The findings suggest that particulate acid phosphatase and phospholipase are compartmentalized in organelles with lysosomal characteristics during development of granular cells and that release of phosphatase is coincident with cornification. This may reflect not only exocytosis of lamellar granules but also intracellular release of the hydrolytic enzyme.