Vesicular PtdIns(3,4,5)P3 and Rab7 are key effectors of sea urchin zygote nuclear membrane fusion.

Vesicular PtdIns(3,4,5)P3 and Rab 7 as key effectors of nuclear membrane assembly

Localization of agonist-sensitive PtdIns(3,4,5)P3 reveals a nuclear pool that is insensitive to PTEN expression.

Phosphatidylinositol (3,4,5) trisphosphate [PtdIns(3,4,5)P3] is a lipid second messenger, produced by Type I phosphoinositide 3-kinases (PI 3-kinases), which mediates intracellular responses to many growth factors. Although PI 3-kinases are implicated in events at both the plasma membrane and intracellular sites, including the nucleus, direct evidence for the occurrence of PtdIns(3,4,5)P3 at no...

Class IA Phosphatidylinositol 3-Kinase p110α Regulates Phagosome Maturation

Of the various phosphatidylinositol 3- kinases (PI3Ks), only the class III enzyme Vps34 has been shown to regulate phagosome maturation. During studies of phagosome maturation in THP-1 cells deficient in class IA PI3K p110α, we discovered that this PI3K isoform is required for vacuole maturation to progress beyond acquisition of Rab7 leading to delivery of lysosomal markers. Bead phagosomes fro...

FYVE-finger proteins

Many biochemical processes in the cell occur at the interface between the cytosol and an intracellular membrane. Vesicular trafficking, signal transduction and actin-regulated membrane rearrangements are examples of processes that require the recruitment of cytosolic proteins to a specific membrane in a reversible and regulated manner. Such a recruitment is in part accomplished through the bind...

Endomembrane PtdIns(3,4,5)P3 activates the PI3K-Akt pathway.

PKB/Akt activation is a common step in tumour growth, proliferation and survival. Akt activation is understood to occur at the plasma membrane of cells in response to growth factor stimulation and local production of the phosphoinositide lipid phosphatidylinositol (3,4,5)-trisphosphate [PtdIns(3,4,5)P3] following phosphoinositide 3-kinase (PI3K) activation. The metabolism and turnover of phosph...