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Updated: Jul 25, 2026

Lipid Droplet Isolation for Quantitative Mass Spectrometry Analysis
10:23

Lipid Droplet Isolation for Quantitative Mass Spectrometry Analysis

Published on: April 17, 2017

A mechanism of membrane neutral lipid acquisition by the microsomal triglyceride transfer protein

J Read1, T A Anderson, P J Ritchie

  • 1Molecular Medicine Group, MRC Clinical Sciences Centre, and National Heart and Lung Institute, Imperial College School of Medicine, Hammersmith Hospital, Du Cane Road, London W12 ONN, United Kingdom.

The Journal of Biological Chemistry
|July 14, 2000
PubMed

Insights

Microsomal triglyceride transfer protein (MTP) facilitates lipid transport by binding neutral lipids. Helix A mediates membrane interaction for lipid acquisition, while Helix B aids lipid transfer into the MTP cavity.

Area of Science:

  • Biochemistry
  • Structural Biology
  • Molecular Biology

Background:

  • Microsomal triglyceride transfer protein (MTP) and apolipoprotein B (apoB) are crucial for lipid transport.
  • MTP is essential for assembling and secreting apoB-lipoproteins, vital for intravascular lipid transport.

Purpose of the Study:

  • To predict the three-dimensional structure of MTP's C-terminal lipid-binding cavity.
  • To elucidate the roles of conserved helices A and B in MTP's lipid binding and transfer functions.

Main Methods:

  • Modeled MTP's C-terminal lipid binding cavity structure based on lamprey lipovitellin crystal structure.
  • Utilized site-directed mutagenesis to study the function of Helix A, Helix B, and the N780Y mutation.

Main Results:

  • MTP's lipid binding cavity shares similarities with intracellular lipid-binding proteins.
  • Helix A insertion into membranes is necessary for neutral lipid acquisition, similar to viral fusion peptides.
  • Helix B is required for transferring lipids into the MTP cavity, while Helix A is critical for initial membrane interaction.

Conclusions:

  • Helix A mediates MTP's interaction with membranes for lipid acquisition.
  • Helix B facilitates the transfer of lipids into MTP's binding cavity.
  • Understanding MTP structure-function relationships is key for developing therapies for lipid metabolism disorders.

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