Cells of the immune system are activated by a variety of stimuli that are derived from other cells, ingested material or from invading microorganisms. This issue of CTMI focuses on the mechanisms of phosphoinositide-mediated protein recruitment to intracellular membranes.
The reversible recruitment of intracellular protein complexes to membranes is essential for immune cell functions, including chemotaxis, phagocytosis and signalling. Such recruitment is often controlled by phosphorylated derivatives of phosphatidylinositol, known as phosphoinositides. These lipids also serve to activate enzyme systems that carry out complex reactions such as chromatin remodelling and pre-mRNA procesing. This issue of Current Topics in Microbiology and Immunology presents an overview of how phosphoinositides function in protein recruitment and enzyme activation and presents physiologically important examples of protein-phosphoinositide interactions.
Preface.- Phosphoinositide involvement in phagocytosis and phagosome maturation.- Regulation of endocytosis by phosphatidylinositol 4,5-biphosphate and ENTH proteins.- Membrane targeting by pleckstrin homology (PH) domains.- Protein targeting to endosomes and phagosomes via FYVE and PX domains.- Regulation of the actin cytoskeleton by PI(4,5)P2 and PI(3,4,5)P3.- Roles of PI3K in neutrophil function.- Nuclear phosphoinositides and their functions.- Subject index.