Ryals P E, Kersting M C
Department of Biochemistry and Molecular Biology, Mississippi State University, Mississippi State 39762, USA.
Arch Biochem Biophys. 1999 Jun 15;366(2):261-6. doi: 10.1006/abbi.1999.1211.
[3H]Scyllo-inositol was taken up by Tetrahymena cells through a sodium-dependent pathway wherein unlabeled scyllo- and myo-inositol competed for uptake. d-Glucose was a competitor of [3H]myo-inositol uptake, but did not appear to compete for [3H]scyllo-inositol uptake. Transport of [3H]scyllo- and [3H]myo-inositol was inhibited when sodium was removed from the labeling buffer and by phlorizin, an inhibitor of sodium-dependent transporters. Cytochalasin B, an inhibitor of facilitated glucose transporters, had no significant effect on inositol transport. Internalized [3H]scyllo-inositol was readily incorporated intact into phosphatidylinositol, phosphatidylinositol-linked glycans, and polyphosphoinositols. Distribution of [3H]scyllo- and [3H]myo-inositol radioactivity into individual polyphosphoinositols was found to differ.
[3H]异肌醇通过一种钠依赖性途径被四膜虫细胞摄取，其中未标记的异肌醇和肌醇竞争摄取。d-葡萄糖是[3H]肌醇摄取的竞争者，但似乎不竞争[3H]异肌醇的摄取。当从标记缓冲液中去除钠以及使用钠依赖性转运蛋白抑制剂根皮苷时，[3H]异肌醇和[3H]肌醇的转运受到抑制。促进性葡萄糖转运蛋白的抑制剂细胞松弛素B对肌醇转运没有显著影响。内化的[3H]异肌醇很容易完整地掺入磷脂酰肌醇、磷脂酰肌醇连接聚糖和多磷酸肌醇中。发现[3H]异肌醇和[3H]肌醇放射性在各个多磷酸肌醇中的分布有所不同。
