iBB
47.5K views | +2 today
Follow
iBB
Institute for Bioengineering and Biosciences
Curated by iBB
Your new post is loading...
Your new post is loading...
Scoop.it!

Quantitative FRET Microscopy Reveals a Crucial Role of Cytoskeleton in Promoting PI(4,5)P2 Confinement

Quantitative FRET Microscopy Reveals a Crucial Role of Cytoskeleton in Promoting PI(4,5)P2 Confinement | iBB | Scoop.it

Phosphatidylinositol 4,5-bisphosphate (PI(4,5)P2) is crucial to many cellular processes in eukaryotes, including membrane trafficking, signal transduction, ion channel function  and cytoskeleton dynamics. This function multiplicity is partially achieved through a dynamic spatiotemporal organization of PI(4,5)P2 within the membrane. In a recent paper published in IJMS, an IBB team (Maria J. Sarmento, Luís Borges-Araújo, Sandra N.Pinto, Nuno Bernardes, Joana Ricardo, Ana Coutinho, Manuel Prieto and Fábio Fernandes) was able to quantify PI(4,5)P2 confinement in living cells making use of FRET imaging measurements. PI(4,5)P2 was found to be significantly compartmentalized at the plasma membrane of HeLa cells. These PI(4,5)P2 enriched domains were shown to not depend on cholesterol content, ruling out an association with lipid rafts. On the other hand, upon inhibition of actin polymerization, compartmentalization of PI(4,5)P2 was almost entirely eliminated, confirming that the cytoskeleton network is the critical component responsible for the formation of nanoscale PI(4,5)P2 domains.

No comment yet.
Scoop.it!

Lipid Hydroperoxide Compromises the Membrane Structure Organization

Lipid Hydroperoxide Compromises the Membrane Structure Organization | iBB | Scoop.it

Lipid hydroperoxides have recently been recognized as key mediators of diseases (such as neurodegenerative disorders or Type II diabetes) and cell death. In a recent work, structural and dynamic perturbations induced by the hydroperoxidized POPC lipid (POPC-OOH) in fluid POPC membranes were addressed using advanced small-angle X-ray scattering (SAXS) and fluorescence methodologies. Notably, this multidisciplinary approach revealed that the hydroperoxide group located at the membrane interface, promotes a higher membrane hydration and microviscosity, with a strikingly lower order and bending rigidity, an unusual trend in membrane biophysics, which ultimately compromises membrane structure organization. This international work co-led by Ana M. Melo (BSIRG-iBB) and Rosangela Itri (Institute of Physics, University of São Paulo) was recently published in Langmuir and involved other BSIRG-iBB researchers (Ana Coutinho, Alexander Fedorov and Manuel Prieto).

No comment yet.