Jove
Visualize
Contact Us
JoVE
x logofacebook logolinkedin logoyoutube logo
ABOUT JoVE
OverviewLeadershipBlogJoVE Help Center
AUTHORS
Publishing ProcessEditorial BoardScope & PoliciesPeer ReviewFAQSubmit
LIBRARIANS
TestimonialsSubscriptionsAccessResourcesLibrary Advisory BoardFAQ
RESEARCH
JoVE JournalMethods CollectionsJoVE Encyclopedia of ExperimentsArchive
EDUCATION
JoVE CoreJoVE BusinessJoVE Science EducationJoVE Lab ManualFaculty Resource CenterFaculty Site
Terms & Conditions of Use
Privacy Policy
Policies

Related Concept Videos

Biosynthesis of Lipids01:29

Biosynthesis of Lipids

882
Microbial membranes exhibit remarkable diversity in lipid composition, reflecting evolutionary adaptations to various environmental conditions. The three domains of life—Bacteria, Archaea, and Eukarya—synthesize membrane lipids through distinct biosynthetic pathways, leading to fundamental structural differences that impact membrane stability, function, and adaptability.Fatty Acid-Based Lipids in Bacteria and EukaryaBacteria and eukaryotes share a common fatty acid biosynthesis...
882
Lipids as Anchors01:32

Lipids as Anchors

8.0K
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...
8.0K
Membrane Fluidity01:26

Membrane Fluidity

18.0K
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...
18.0K
Membrane Fluidity01:23

Membrane Fluidity

179.5K
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.
179.5K
Mechanisms of Membrane Domain Formation00:59

Mechanisms of Membrane Domain Formation

4.4K
Different physical properties of lipids and proteins allow them to localize and form distinct islands or domains in the membrane. Some membrane domains are formed due to protein-protein interactions, whereas others are formed due to the presence of specific lipids such as sphingolipids and sterols—for example, large proteins, such as bacteriorhodopsin, aggregate and create distinct domains.
Another mechanism for membrane domain formation involves membrane proteins interacting with...
4.4K
Membrane Lipids01:32

Membrane Lipids

35.6K
Lipids are an essential component of all biological membranes. The average lipid content in mammalian membranes is 50%, though it can be as low as 20% in the inner mitochondrial membrane or as high as 80% in the myelin sheath present around the nerve cells.
Phosphatidylcholine, phosphatidylethanolamine, phosphatidylserine, and sphingomyelin are the most common phospholipids present in mammalian membranes. At physiological pH, phosphatidylserine is negatively charged, while the other three...
35.6K

You might also read

Related Articles

Articles linked to this work by shared authors, journal, and citation graph.

Sort by
Same author

Protocol for the quantification of digestive exophagy in cell culture.

STAR protocols·2026
Same author

Retraction Note: Inhibition of alpha-synuclein seeded fibril formation and toxicity by herbal medicinal extracts.

BMC complementary medicine and therapies·2025
Same author

Real-time pH imaging of macrophage lysosomes using the pH-sensitive probe ApHID.

Cell reports methods·2025
Same author

Real-time pH imaging of macrophage lysosomes using the pH-sensitive probe ApHID.

Cell reports methods·2025
Same author

Genetic code expansion and enzymatic modifications as accessible methods for studying site-specific post-translational modifications of alpha-synuclein and tau.

Protein science : a publication of the Protein Society·2025
Same author

An Amyloidogenic Fragment of the Spike Protein from SARS-CoV-2 Virus Stimulates the Aggregation and Toxicity of Parkinson's Disease Protein Alpha-Synuclein.

ACS chemical neuroscience·2025
Same journal

Aromatic Cage-Directed Azide-Methyllysine Photochemistry for Profiling Nonhistone Interacting Partners of the MeCP2 Methyl-CpG-Binding Domain.

Biochemistry·2026
Same journal

Differential Hydroxypyruvate Processing by <i>E. coli</i> and <i>P. aeruginosa</i> DXP Synthases Reveals Preferential Xylulose 5-Phosphate Formation by the <i>P. aeruginosa</i> Enzyme.

Biochemistry·2026
Same journal

Structural and Functional Characterization of Heterologous Nitrogenase Complexes.

Biochemistry·2026
Same journal

Discovery of Bacterial Unspecific Peroxygenases.

Biochemistry·2026
Same journal

Lactate Biology: Subcellular Routing and Chemical Form Define Function.

Biochemistry·2026
Same journal

Nature's Anaerobic Toolkit: Glycyl Radical Enzymes and Their Expanding Functional and Mechanistic Diversity.

Biochemistry·2026
See all related articles

Related Experiment Video

Updated: Apr 7, 2026

Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes
08:49

Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes

Published on: March 14, 2021

4.8K

STARD4 Membrane Interactions and Sterol Binding.

David B Iaea1,2, Igor Dikiy1, Irene Kiburu3

  • 1†Department of Biochemistry, Weill Cornell Medical College, 1300 York Avenue, New York, New York 10065, United States.

Biochemistry
|July 14, 2015
PubMed
Summary
This summary is machine-generated.

Steroidogenic acute regulatory protein-related lipid transfer (START) domain proteins like STARD4 transport sterols. This study reveals STARD4

More Related Videos

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures
11:44

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures

Published on: September 28, 2013

14.9K
Construction of Model Lipid Membranes Incorporating G-protein Coupled Receptors GPCRs
09:45

Construction of Model Lipid Membranes Incorporating G-protein Coupled Receptors GPCRs

Published on: February 5, 2022

4.1K

Related Experiment Videos

Last Updated: Apr 7, 2026

Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes
08:49

Fluorescence-Based Measurements of Phosphatidylserine/Phosphatidylinositol 4-Phosphate Exchange Between Membranes

Published on: March 14, 2021

4.8K
Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures
11:44

Metabolic Labeling and Membrane Fractionation for Comparative Proteomic Analysis of Arabidopsis thaliana Suspension Cell Cultures

Published on: September 28, 2013

14.9K
Construction of Model Lipid Membranes Incorporating G-protein Coupled Receptors GPCRs
09:45

Construction of Model Lipid Membranes Incorporating G-protein Coupled Receptors GPCRs

Published on: February 5, 2022

4.1K

Area of Science:

  • Biochemistry
  • Molecular Biology
  • Structural Biology

Background:

  • Steroidogenic acute regulatory protein-related lipid transfer (START) domain proteins are crucial for lipid transport and metabolism.
  • STARD4, a soluble START protein, facilitates sterol transfer, but its membrane interaction and binding mechanisms are not fully understood.

Purpose of the Study:

  • To biochemically and structurally characterize STARD4's membrane interaction and sterol binding mechanisms.
  • To elucidate the role of specific regions, including the Omega-1 (Ω1) loop and C-terminal α-helix, in STARD4 function.

Main Methods:

  • Biochemical techniques to characterize STARD4 regions.
  • Site-directed mutagenesis (L124D mutation).
  • Structural and biophysical studies (e.g., X-ray crystallography, spectroscopy) of wild-type and mutant STARD4.

Main Results:

  • STARD4 interacts with anionic membranes via a surface-exposed basic patch.
  • A mutation in the Ω1 loop (L124D) attenuates sterol transfer by reducing conformational flexibility and membrane interaction.
  • The C-terminal α-helix, not the Ω1 loop, inserts into the membrane bilayer during sterol transfer.

Conclusions:

  • STARD4's sterol transfer involves dynamic Ω1 loop movement and C-terminal α-helix membrane insertion.
  • The L124D mutation impairs STARD4 function by hindering these dynamic processes.
  • A proposed model details STARD4's membrane interaction, sterol binding, and release mechanism.