Phosphoinositide conversion in endocytosis and the endolysosomal system.
Phosphoinositides (PIs) are phospholipids that perform crucial cell functions, ranging from cell migration and signaling to membrane trafficking, by serving as signposts of compartmental membrane identity. Although phosphatidylinositol 4,5-bisphosphate, 3-phosphate, and 3,5-bisphosphate are commonly considered as hallmarks of the plasma membrane, endosomes, and lysosomes, these compartments contain other functionally important PIs. Here, we review the roles of PIs in different compartments of the endolysosomal system in mammalian cells and discuss the mechanisms that spatiotemporally control PI conversion in endocytosis and endolysosomal membrane dynamics during endosome maturation and sorting. As defective PI conversion underlies human genetic diseases, including inherited myopathies, neurological disorders, and cancer, PI-converting enzymes represent potential targets for drug-based therapies.
['Wallroth|Alexander|A|', 'Haucke|Volker|V|']
D000818:Animals D004705:Endocytosis D011992:Endosomes D006801:Humans D008247:Lysosomes D018129:Phosphatidylinositol Phosphates D015398:Signal Transduction D018631:ras Proteins
endocytosis phosphatidylinositol endosome lysosome autophagy mTOR complex (mTORC) phosphatidylinositol kinase (PI Kinase) phosphatidylinositol phosphatase phosphatidylinositol signaling