Phosphatidylinositol (PI) is an essential structural component of eukaryotic membranes that also serves as the common precursor for polyphosphoinositide (PPIn) lipids. Despite the recognized importance of PPIn species for signal transduction and membrane homeostasis, there is still a limited understanding of the relationship between PI availability and the turnover of subcellular PPIn pools. To address these shortcomings, we established a molecular toolbox for investigations of PI distribution within intact cells by exploiting the properties of a bacterial enzyme, PI-specific PLC (PI-PLC). Using these tools, we find a minor presence of PI in membranes of the ER, as well as a general enrichment within the cytosolic leaflets of the Golgi complex, peroxisomes, and outer mitochondrial membrane, but only detect very low steady-state levels of PI within the plasma membrane (PM) and endosomes. Kinetic studies also demonstrate the requirement for sustained PI supply from the ER for the maintenance of monophosphorylated PPIn species within the PM, Golgi complex, and endosomal compartments.

• MeSH
• bakteriální proteiny genetika   metabolismus   MeSH
• biosenzitivní techniky MeSH
• buněčná membrána metabolismus   MeSH
• Cercopithecus aethiops MeSH
• COS buňky MeSH
• fosfatidylinositolfosfáty metabolismus   MeSH
• fosfatidylinositoly metabolismus   MeSH
• fosfolipasy typu C genetika   metabolismus   MeSH
• HEK293 buňky MeSH
• intracelulární membrány metabolismus   MeSH
• kinetika MeSH
• konfokální mikroskopie MeSH
• lidé MeSH
• luminescentní proteiny genetika   metabolismus   MeSH
• rekombinantní fúzní proteiny genetika   metabolismus   MeSH
• systémy druhého messengeru MeSH
• zvířata MeSH
• Check Tag
• lidé MeSH
• zvířata MeSH
• Publikační typ
• časopisecké články MeSH
• práce podpořená grantem MeSH
• Research Support, N.I.H., Extramural MeSH
• srovnávací studie MeSH