Marche P, Koutouzov S, Meyer P
Biochim Biophys Acta. 1982 Mar 12;710(3):332-40. doi: 10.1016/0005-2760(82)90116-3.
The metabolism of phosphoinositides was investigated in the red blood cell membrane of the rat by measuring 32P-incorporation into phospholipids after incubation of membranes with [gamma-32P]ATP in a medium containing magnesium. A new chromatographic procedure has been developed which facilitates the separation of triphosphoinositide, diphosphoinositide and phosphatidylinositol from the phospholipids present in lipid extracts of incubated 'ghost' under our experimental conditions only two phospholipids, diphosphoinositide and triphosphoinositide, were 32P-labelled. Furthermore, the results indicate that either di-or triphosphoinositide could be labelled preferentially, depending upon the magnesium concentration of the incubation medium. This clarifies some apparent discrepancies reported in the literature between the 32 P labelling of polyphosphoinositides observed in intact erythrocytes and that observed with 'ghost' membranes. In addition, the enzymatic pathways involved in the phosphoinositide metabolism are discussed.
通过在含镁培养基中用[γ-32P]ATP孵育大鼠红细胞膜后，测量32P掺入磷脂的情况，对磷酸肌醇的代谢进行了研究。已开发出一种新的色谱方法，该方法有助于从孵育的“血影”脂质提取物中的磷脂中分离出三磷酸肌醇、二磷酸肌醇和磷脂酰肌醇。在我们的实验条件下，脂质提取物中仅二磷酸肌醇和三磷酸肌醇这两种磷脂被32P标记。此外，结果表明，根据孵育培养基中的镁浓度，二磷酸肌醇或三磷酸肌醇都可以被优先标记。这澄清了文献中报道的完整红细胞中观察到的多磷酸肌醇的32P标记与“血影”膜中观察到的标记之间的一些明显差异。此外，还讨论了磷酸肌醇代谢中涉及的酶促途径。
