Biosynthesis, processing, turnover and distribution of ( <Na^+> , <K^+> ) ATPase

( <Na^ > , <K^ > ) ATPase 的生物合成、加工、周转和分配

基本信息

批准号：
59480099
负责人：
TASHIRO Yutaka
金额：
$ 4.29万
依托单位：
Kansai Medical University
依托单位国家：
日本
项目类别：
Grant-in-Aid for General Scientific Research (B)
财政年份：
1984
资助国家：
日本
起止时间：
1984 至 1986
项目状态：
已结题

来源：
https://kaken.nii.ac.jp/en/grant/KAKENHI-PROJECT-59480099/
关键词：
( <Na^+> , <K^+> )ATPase hepatocyte exocrine pancreatic cell parotide acinar cell cell polarity 生合成プロセッシング

项目摘要

We purified holo( <Na^+> , <K^+> )ATPase from canine and rat kidney outer medulla and prepared monospecific antibody against the ATPase. We investigated the distribution of the ATPase in canine hepatocytes, rat exocrine pancreatic cells and rat parotid cells, and also biosynthesis and processing of the ATPase in rat kidney.1) In canine hepatocytes, ( <Na^+> , <K^+> )ATPase was found not only on the sinusoid-lateral surface but also on the bile canalicular surface and the surface density on the latter was 2.5 times higher than that on the former.2) In the exocrine pancreatic cells, the ATPase was found on the luminal surface of not only acinar cells but also ductal cells, and we suggested that the ATPase actively participates in the formation of the pancreatic fluids.3) In the parotid acinar cells, a small but significant amount of ( <Na^+> , <K^+> )ATPase was found on the luminal surface. In the duct cells, however, the ATPase was distributed exclusively on the basal plasma membrane, especially on the well developed basal infoldings.4) Biosynthesis of the ATPase in rat kidney was investigated by labeling with <^(35)S> -Met and it was revealed that the <beta> subunit (38K) was cotranslationally glycosylated in the ER to form the 50 K high-mannose type glycoprotein and then converted to the 54 K complex type glycoprotein. The molecular weight of the <alpha> subunit (95 K) did not change throughout the intracellular transport and processing.

我们从犬和大鼠肾外髓质中纯化了holo( <Na^+> , <K^+> )ATPase，并制备了针对该ATPase的单特异性抗体。我们研究了犬肝细胞、大鼠外分泌胰腺细胞和大鼠腮腺细胞中 ATP 酶的分布，以及大鼠肾脏中 ATP 酶的生物合成和加工。1) 在犬肝细胞中，( <Na^+> , <K^+> )ATP酶不仅存在于血窦外侧表面，而且存在于胆小管表面，且后者的表面密度是前者的2.5倍。2)在外分泌胰腺细胞中，不仅在腺泡细胞的管腔表面上发现了 ATPase，而且在导管细胞的管腔表面也发现了 ATPase，我们认为 ATPase 积极参与了胰液的形成。 3）在腮腺腺泡细胞中，存在一个虽小但很重要的 ATPase。在管腔表面发现了一定量的 ( <Na^+> , <K^+> )ATPase。然而，在导管细胞中，ATP酶仅分布在基底质膜上，特别是在发育良好的基底内褶上。4)通过用<^(35)S>-Met和标记来研究大鼠肾脏中ATP酶的生物合成。结果表明，<β>亚基（38K）在 ER 中被共翻译糖基化，形成 50 K 高甘露糖型糖蛋白，然后转化为 54 K复合型糖蛋白。 <α>亚基的分子量(95 K)在整个细胞内运输和加工过程中没有变化。