Related Experiment Video

Updated: Aug 11, 2026

Monitoring Cleaved Caspase-3 Activity and Apoptosis of Immortalized Oligodendroglial Cells using Live-cell Imaging and Cleaveable Fluorogenic-dye Substrates Following Potassium-induced Membrane Depolarization
10:45

Monitoring Cleaved Caspase-3 Activity and Apoptosis of Immortalized Oligodendroglial Cells using Live-cell Imaging and Cleaveable Fluorogenic-dye Substrates Following Potassium-induced Membrane Depolarization

Published on: January 13, 2012

Concerted modulation by myelin basic protein and sulfatide of the activity of phospholipase A2 against phospholipid

I D Bianco1, G D Fidelio, R K Yu

  • 1Departmento de Quimica Biologica-CIQUIBIC, Facultad de Ciencias Quimicas-CONICET, Universidad Nacional de Cordoba, Argentina.

Biochemistry
|March 17, 1992
PubMed

Insights

Myelin basic protein (MBP) significantly alters phospholipase A2 (PLA2) activity. Its effects on lipid degradation depend on phospholipid type and MBP concentration, with charge interactions playing a key role.

Area of Science:

  • Biochemistry
  • Lipid Metabolism
  • Enzyme Kinetics

Background:

  • Phospholipase A2 (PLA2) is crucial for lipid hydrolysis.
  • Myelin basic protein (MBP) is a key component of myelin sheaths.
  • The interaction between MBP and PLA2 in lipid environments is not fully understood.

Purpose of the Study:

  • To investigate the impact of myelin basic protein (MBP) on phospholipase A2 (PLA2) activity.
  • To determine how MBP influences PLA2's degradation of specific phospholipids (dlPC, dlPA) in mixed monolayers.
  • To elucidate the role of glycolipids (sulfatide, galactocerebroside) in modulating MBP-PLA2 interactions.

Main Methods:

  • Investigated PLA2 activity against lipid monolayers containing varying proportions of dilauroylphosphatidylcholine (dlPC) or dilauroylphosphatidic acid (dlPA), sulfatide (Sulf), and galactocerebroside (GalCer).
  • Introduced MBP via direct spreading or adsorption into lipid monolayers.
  • Analyzed enzyme activity based on MBP mole fraction and lipid composition.

Main Results:

  • MBP's effect on PLA2 activity is dependent on phospholipid type and MBP concentration.
  • At low MBP concentrations, dlPA degradation is inhibited, likely due to charge interactions, while dlPC degradation is minimally affected.
  • Increased MBP concentrations lead to enhanced PLA2 activity, particularly when distinct lipid-protein domains form.
  • Galactocerebroside (GalCer) showed minimal influence, while sulfatide (Sulf) modulated MBP's effect, balancing interactions.

Conclusions:

  • MBP modulates PLA2 activity through concentration-dependent mechanisms and interactions with specific phospholipids.
  • Charge-based interactions between MBP and dlPA significantly inhibit PLA2.
  • The interplay between MBP, sulfatide, and phospholipids allows for fine-tuned regulation of PLA2 activity in lipid interfaces.

More Related Videos

Multifunctional, Micropipette-based Method for Incorporation And Stimulation of Bacterial Mechanosensitive Ion Channels in Droplet Interface Bilayers09:54

Multifunctional, Micropipette-based Method for Incorporation And Stimulation of Bacterial Mechanosensitive Ion Channels in Droplet Interface Bilayers

Published on: November 19, 2015

A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA210:31

A Liposome Membrane Permeability Assay for Investigating the Effects of Phosphatidylinositol Phosphate Groups on Membranotropic Action of Venom PLA2

Published on: September 26, 2025

Related Concept Videos

Membrane Fluidity01:23

Membrane Fluidity

Cell membranes are composed of phospholipids, proteins, and carbohydrates loosely attached to one another through chemical interactions. Molecules are generally able to move about in the plane of the membrane, giving the membrane its flexible nature called fluidity. Two other features of the membrane contribute to membrane fluidity: the chemical structure of the phospholipids and the presence of cholesterol in the membrane.Fatty acids tails of phospholipids can be either saturated or...
Membrane Fluidity01:26

Membrane Fluidity

Membrane fluidity is explained by the fluid mosaic model of the cell membrane, which describes the plasma membrane structure as a mosaic of components—including phospholipids, cholesterol, proteins, and carbohydrates—that gives the membrane a fluid character.
Mosaic nature of the membrane
The mosaic characteristic of the membrane helps the plasma membrane remain fluid. The integral proteins and lipids exist as separate but loosely-attached molecules in the membrane. The membrane is a relatively...
Fluid Mosaic Model01:19

Fluid Mosaic Model

Scientists identified the plasma membrane in the 1890s and its principal chemical components (lipids and proteins) by 1915. The model for plasma membrane structure, proposed in 1935 by Hugh Davson and James Danielli, was the first model to be widely accepted in the scientific community. The model was based on the plasma membrane's "railroad track" appearance in early electron micrographs. Davson and Danielli theorized that the plasma membrane's structure resembled a sandwich with the analogy of...
Asymmetric Lipid Bilayer01:35

Asymmetric Lipid Bilayer

Biological membranes show uneven distribution of different types of lipids in the inner and outer layers, resulting in transverse asymmetric membranes. The treatment of the erythrocyte membrane with the enzyme phospholipase confirmed the asymmetric nature of the lipid bilayer. The enzyme hydrolyzes lipids into fatty acids and hydrophilic groups. The phospholipase acts only on the outer layer of the membrane, while the inner layer remains intact. The phospholipase treatment resulted in 80%...
Phosphoinositides and PIPs01:42

Phosphoinositides 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...
IP3/DAG Signaling Pathway01:11

IP3/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...