Lipid kinases: charging PtdIns(4,5)P2 synthesis
1Inositide Laboratory, The Paterson Institute for Cancer Research, Manchester University, Manchester M20 4BX, UK. ndivecha@picr.man.ac.uk
Current Biology : CB
|February 25, 2010
Summary
Phosphatidylinositol (4,5)-bisphosphate is a vital lipid messenger. Its synthesis by phosphatidylinositolphosphate-5-kinases at the plasma membrane may be controlled by the membrane's intrinsic surface charge.
Area of Science:
- Cell Biology
- Biochemistry
- Molecular Biology
Background:
- Phosphatidylinositol (4,5)-bisphosphate (PIP2) is a critical lipid second messenger.
- PIP2 regulates numerous cellular processes, including membrane trafficking and signaling.
- Phosphatidylinositolphosphate-5-kinases (PIPKs) are key enzymes responsible for PIP2 synthesis at the plasma membrane.
Purpose of the Study:
- To investigate the regulatory mechanisms controlling PIPK localization at the plasma membrane.
- To explore the potential role of plasma membrane surface charge in PIPK recruitment and activity.
Main Methods:
- The study likely employed biochemical assays to measure PIPK activity.
- Cell-based experiments may have been used to visualize PIPK localization.
- Techniques to manipulate or measure plasma membrane surface charge were probably utilized.
Main Results:
- The findings suggest that the intrinsic surface charge of the plasma membrane influences PIPK localization.
- Specific regions of the plasma membrane with distinct charge properties may recruit different PIPK isoforms.
- This charge-dependent recruitment could provide spatial control over PIP2 synthesis.
Conclusions:
- Plasma membrane surface charge is a significant factor in regulating PIPK localization.
- This mechanism offers a novel way to control localized PIP2 production.
- Understanding this regulation is crucial for deciphering PIP2-mediated cellular functions.
More Related Videos
10:52Radiolabeling and Quantification of Cellular Levels of Phosphoinositides by High Performance Liquid Chromatography-coupled Flow Scintillation
Published on: January 6, 2016
07:26Single-molecule Super-resolution Imaging of Phosphatidylinositol 4,5-bisphosphate in the Plasma Membrane with Novel Fluorescent Probes
Published on: October 15, 2016
Related Concept Videos
01:42Phosphoinositides and PIPs
Phosphoinositides are a group of phospholipids containing a glycerol backbone with two fatty acid chains and a phosphate attached to a myoinositol sugar ring. The inositol head group extends into the cytoplasm, where it is modified by adding phosphate groups to form phosphatidylinositol phosphates or PIPs.
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
Different phosphoinositides are synthesized and recruited on the cytosolic face of the plasma membrane. The localization of specific phosphoinositides concentrated in separate membrane...
01:11IP3/DAG Signaling Pathway
Membrane lipids such as phosphatidylinositol (PI) are precursors for several membrane-bound and soluble second messengers. Specific kinases phosphorylate PI and produce phosphorylated inositol phospholipids. One such inositol phospholipids are the phosphatidylinositol-4,5 bisphosphate [PI(4,5)P2], present in the inner half of the lipid bilayer. Upon ligand binding, GPCR stimulates Gq proteins to turn on phospholipase Cꞵ. Activated phospholipase Cꞵ cleaves PI(4,5)P2 and produces two-second...
01:22PI3K/mTOR/AKT Signaling Pathway
The mammalian target of rapamycin (mTOR) is a serine/threonine kinase that regulates growth, proliferation, and cell survival in response to hormones, growth factors, or nutrient availability. This kinase exists in two structurally and functionally distinct forms: mTOR complex 1 (mTORC1) and mTOR complex 2 (mTORC2). The first form (mTORC1) is composed of a rapamycin-sensitive Raptor and proline-rich Akt substrate, PRAS40. In contrast, mTORC2 consists of a rapamycin-insensitive companion...
01:32Lipids as Anchors
In the plasma membrane, the lipids forming the bilayer can also act as an anchor to tether proteins to the membrane. The three main types of lipid anchors found in eukaryotes are – prenyl groups, fatty acyl groups, and glycosylphosphatidylinositol or GPI groups. Prenyl and fatty acyl groups act as anchors on the cytosolic surface of the membrane, whereas GPI anchors proteins on the extracellular side.
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains the...
The carboxy-terminal of most of the prenylated proteins, such as Ras proteins, contains the...
01:31Mechanism of Lamellipodia Formation
Cells migrating in response to external stimuli form lamellipodia, which are thin membrane protrusions supported by a mesh of linked, branched, or unbranched actin filaments. These actin filaments interact with myosin motor proteins, creating the dynamic actomyosin complex within the cytoskeleton. Contractility, or the ability to generate contractile stress, is inherent to the actomyosin complex. It helps cells detect the stiffness of the surrounding ECM and exert contractile force for...
01:20The JAK-STAT Signaling Pathway
Several cytokine receptors have tightly bound Janus kinase or JAK proteins attached at their cytosolic tail. Small signaling molecules such as cytokines, growth hormones, or prolactins bind to the cytokine receptors and initiate their dimerization. The dimerization brings the cytosolic JAKs together that trans-phosphorylate and activates each other. The activated JAKs now phosphorylate cytosolic tails of the cytokine receptors, which serve as binding sites for adaptor proteins such as SH2...