Faculty Collaboration Database

Nanoscale Landscape of Phosphoinositides Revealed by Specific Pleckstrin Homology (PH) Domains Using Single-molecule Superresolution Imaging in the Plasma Membrane. J Biol Chem 2015 Nov 06;290(45):26978-26993

Date

09/24/2015

Pubmed ID

26396197

Pubmed Central ID

PMC4646391

DOI

10.1074/jbc.M115.663013

Scopus ID

2-s2.0-84946780726 (requires institutional sign-in at Scopus site)   43 Citations

Abstract

Both phosphatidylinositol 4-phosphate (PI4P) and phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) are independent plasma membrane (PM) determinant lipids that are essential for multiple cellular functions. However, their nanoscale spatial organization in the PM remains elusive. Using single-molecule superresolution microscopy and new photoactivatable fluorescence probes on the basis of pleckstrin homology domains that specifically recognize phosphatidylinositides in insulin-secreting INS-1 cells, we report that the PI(4,5)P2 probes exhibited a remarkably uniform distribution in the major regions of the PM, with some sparse PI(4,5)P2-enriched membrane patches/domains of diverse sizes (383 ± 14 nm on average). Quantitative analysis revealed a modest concentration gradient that was much less steep than previously thought, and no densely packed PI(4,5)P2 nanodomains were observed. Live-cell superresolution imaging further demonstrated the dynamic structural changes of those domains in the flat PM and membrane protrusions. PI4P and phosphatidylinositol (3,4,5)-trisphosphate (PI(3,4,5)P3) showed similar spatial distributions as PI(4,5)P2. These data reveal the nanoscale landscape of key inositol phospholipids in the native PM and imply a framework for local cellular signaling and lipid-protein interactions at a nanometer scale.

Author List

Ji C, Zhang Y, Xu P, Xu T, Lou X

Author

Xuelin Lou PhD Professor in the Cell Biology, Neurobiology and Anatomy department at Medical College of Wisconsin

MESH terms used to index this publication - Major topics in bold

Animals
COS Cells
Cell Line
Cell Membrane
Insulin-Secreting Cells
Luminescent Proteins
Membrane Proteins
Microtubules
Nanotechnology
Phosphatidylinositol 4,5-Diphosphate
Phosphatidylinositol Phosphates
Phosphatidylinositols
Protein Structure, Tertiary
Rats
Signal Transduction
Syntaxin 1